Compared with the control group, the CPP and CPA groups showed a significant increase of c-Fos expression in the dorsomedial striatum, central medial nucleus of the thalamus, and the basolateral amygdala. 
A similar interaction between MPN lesions and testosterone occurred on AVP mRNA levels in the medial nucleus of the amygdala.
Additionally, a medial hypothalamic defensive circuit also appears not necessary for unconditioned freezing to TMT, whereas circuits that include the medial nucleus of the amygdala and the bed nucleus of the stria terminalis are essential.
In addition, a few studies have reported an involvement of the basolateral and medial nucleus of the amygdala and hippocampus in fear conditioning.
Inactivation of the olfactory system and medial nucleus of the amygdala, combined with induction of the immediate-early gene c-fos, suggest the necessity of the accessory olfactory system in mediating the effects of ferret odor.
Results demonstrate that animals pre-treated with CTAP into the nucleus accumbens core or rostral VTA, but not the caudal VTA, caudate putamen or medial nucleus accumbens shell, during conditioning with cocaine showed an attenuation of the development of cocaine-induced place preference.
The anterodorsal (MeAD) and posteroventral (MePV) subnuclei would form the proposed "ventral" division of the rat medial nucleus of the amygdala (MeA).
METHODS: We determined the basal mRNA and protein levels of BDNF by in situ RT-PCR and immuno-histochemical procedure, respectively, in the amygdaloid [ central nucleus of amygdala (CeA), medial nucleus of amygdala (MeA), and basolateral amygdala (BLA)], nucleus accumbal (NAc shell and core), and bed nucleus of stria terminalis (BNST) [ lateral BNST (lBNST), medial BNST (mBNST), and ventral BNST (vBNST)] brain structures of P and NP rats.
The aim of this study was the analysis of cytoarchitectonics, neuronal organization and gender factor influence on neuronal dendroarchitectonics of amygdala posterior medial nucleus.
As adults, neonatal GDX rats also showed a decrease in the number of androgen receptor and arginine vasopressin-positive cells in the bed nucleus of the stria terminalis and in the medial nucleus of the amygdala, and both of these responses were reversed with postnatal testosterone treatment.
Blocking the observed increase in HDAC activity during alcohol withdrawal with the HDAC inhibitor, trichostatin A, rescued the deficits in H3 and H4 acetylation and NPY expression (mRNA and protein levels) in the amygdala (central and medial nucleus of amygdala) and prevented the development of alcohol withdrawal-related anxiety in rats as measured by the elevated plus maze and light/dark box exploration tests.
In sections labeled for TH, large accumulations of silver grains were admixed with TH-labeled processes in the medial nucleus of the amygdala and over TH-labeled perikarya in the medial and commissural nucleus of the solitary tract.
In the amygdaloid complex, GAD65 is strongly expressed in striatal-like divisions, namely, the anterior amygdaloid area, the central nucleus (CEA), the intercalated nuclei, and the dorsal part of the medial nucleus (MEA). VGLUT1 and -2 expression is mostly segregated to specific divisions of the amygdale, with VGLUT2 being expressed only in the MEA, the anterior cortical nucleus (COAa), and the anterior basomedial nucleus (BMAa), whereas VGLUT1 is expressed in all other divisions of the amygdala.
Rats received an anorexigenic dose of PYY(3-36), and the number of neurons expressing Fos, an indicator of neuronal activation, was determined in anterior hypothalamus (AH), arcuate nucleus (ARC), dorsomedial hypothalamus (DMH), lateral hypothalamus (LH), ventromedial hypothalamus (VMH), central nucleus of the amygdala (CeA), area postrema (AP), and caudal medial nucleus tractus solitarius (cmNTS), commissural NTS (cNTS), and gelatinosus NTS (gNTS).
RESULTS AND DISCUSSION: The greatest number of galanin-immunoreactive neurons were identified in the medial part of the central nucleus and in the dorsal part of the medial nucleus. GAL-immunoreactive fibers were identified in the medial nucleus, "bed nucleus" of the accessory olfactory tract, fiontal cortical nucleus, amygdalo-hippocampal area and basolateral nucleus. VIP-immunoreactive neurons were diffusely distributed in more nuclei than the previous, mostly in the lateral, basolateral, and basomedial nucleus. CONCLUSION: By distribution analysis of GAL and VIP immunoreactive neurons and fibers, and according to literature data, it can be assumed that the medial part of the central nucleus receives VIP fibers from other parts of the amygdaloid body, and then sends GAL fibers to the medial nucleus..
It has been shown that facilitation of GABA-mediated neurotransmission in the medial nucleus of the amygdala and the dorsal periaqueductal gray (dPAG) inhibits the escape, but not the inhibitory avoidance response generated in the elevated T-maze test of anxiety (ETM).
We investigated whether puberty influences the morphology of the medial nucleus of the amygdala (MeA) by comparing Siberian hamsters (Phodopus sungorus) that had been raised from birth in either long day (LD; 16:8 h light:dark) or short day (SD; 8:16) photoperiods.
Fos-li in the medial nucleus of the amygdala and the dorsal lateral septum also distinguished 2DG-induced torpor from other 2DG-induced behaviors.
nociceptin produced a significant increase in Fos staining in the dorsomedial nucleus of the hypothalamus, the perinuclear zone of the supraoptic nucleus, the organum vasculosum of the lamina terminalis (OVLT), the lateral preoptic area and the lateral hypothalamic area compared to control. Furthermore, ICER staining was significantly increased in the perinuclear zone of the supraoptic nucleus, supraoptic nucleus, median preoptic nucleus, OVLT, medial preoptic area, central nucleus of the amygdala, and medial nucleus of the solitary tract.
Fifteen days following surgery, prepro-neuropeptide Y (NPY) mRNA levels were significantly increased in the hypothalamus of bulbectomized OM rats and in the medial nucleus of the amygdala of bulbectomized OM and S5B/Pl rats. OBX decreased NPY Y2 receptor mRNA levels in the hypothalamus and medial nucleus of the amygdala in OM rats, while increasing NPY Y2 receptor mRNA levels in the medial nucleus of the amygdala of S5B/Pl rats.
The basolateral (BLA) and medial nucleus (MeA) of the amygdala participate in the modulation of unconditioned fear induced by predator odor.
The mSPFp is reciprocally connected to the medial preoptic area (MPOA), bed nucleus of the stria terminalis (BNST) and the medial nucleus of the amygdala (Me), all of which are critical for the regulation of male sexual behavior.
Control injections were made in the central medial nucleus (CEM) of the thalamus.
In the last years, the role played by the medial nucleus of the amygdala (MeA) in the modulation of fear- and anxiety-related behaviors has been increasingly investigated.
Pup exposure and parity also enhanced activation of the nucleus accumbens shell and medial nucleus of the amygdala, respectively.
Our findings indicate that the magnocellular medial preoptic nucleus receives 1) chemosensory input from areas in the main and accessory olfactory pathways including the posterior medial bed nucleus of the stria terminalis, anterior medial, anterior cortical and posterior cortical nuclei of the amygdala; 2) input from steroid responsive structures such as the posterior medial nucleus of the amygdala, bed nucleus of the stria terminalis, lateral septum, anteroventral periventricular nucleus, medial preoptic nucleus, ventromedial nucleus of the hypothalamus and arcuate nucleus; 3) input from structures in the brainstem such as the subparafascicular thalamic nucleus, peripeduncular nucleus and the premamillary nucleus in the hypothalamus that carry sensory information from the genitalia. The major afferent input to the magnocellular medial preoptic nucleus was confirmed by injecting anterograde tracer biotinylated dextran amine into the anterior medical nucleus of the amygdala, the posterodorsal part of the medial nucleus of the amygdala, the posteromedial part of the bed nucleus of the stria terminalis and the posterointermediate part of the bed nucleus of the stria terminalis.
Neurons expressing Ucn 3 mRNA and peptide are distributed in specific brain areas, including the median preoptic nucleus, the perifornical area (PFx), and the medial nucleus of the amygdala (MEA).
Furthermore, females that received a single injection of testosterone 1 day after birth showed significant increases in the density of oxytocin binding sites in the ventromedial hypothalamic nucleus, medial nucleus of the amygdala and medial bed nucleus of the stria terminalis.
The nucleus of the lateral olfactory tract could not be definitively identified and the medial nucleus of amygdala appeared to be very small in the echidna.
The posterodorsal part of the medial nucleus of the amygdala (MEApd) and the principal nucleus of the BST (BSTpr) share strong birectional connections that project primarily through the stria terminalis.
Although autoradiographic studies using the oxytocin receptor antagonist [ (125)I]d(CH(2))(5)[ Tyr(Me)(2),Thr(4),Orn(8),Tyr-NH(2)(9)]-vasotocin showed a higher density of binding in the central nucleus of the amygdala than medial nucleus of the amygdala, neurones in the central nucleus of the amygdala had a much lower sensitivity to oxytocin: equivalent responses obtained with 10(-6)M in the central nucleus of the amygdala and 10(-8)M in the medial nucleus of the amygdala, and neurones in the central nucleus of the amygdala were insensitive to concentrations below 10(-6)M. Furthermore, repeated applications of oxytocin induced homologous desensitization in the central nucleus of the amygdala, but not medial nucleus of the amygdala-a single application of oxytocin producing long duration suppression of responses. Studies made across the reproductive cycle showed that lactating animals exhibited a larger proportion of oxytocin-responsive neurones in the medial nucleus of the amygdala and a smaller proportion in the central nucleus of the amygdala, compared with virgin or pregnant animals, indicating a peripartum shift in relative activation within the amygdala.
Expression of c-Fos in the amygdala (the central nucleus, CeA; the medial nucleus, MeA; the basolateral nucleus, BLA) following naloxone-precipitated withdrawal and the CPA test was examined using a range of naloxone doses (0.02, 0.05, 0.1, 0.2, 0.5 and 1.0 mg/kg).
Four hormone-responsive nuclei are considered: The spinal nucleus of the bulbocavernosus (SNB), the medial nucleus of the amygdala (MeA), the ventromedial nucleus of the hypothalamus (VMN), and the CA1 region of the dorsal hippocampus.
Researchers have found that stimulation of the medial nucleus of the amygdala (MeA) in male rats increases appetitive copulatory behavior directed toward an anestrous female but suppresses copulation with an estrous female (C.
Examination of the regional distribution of MAO-B revealed lower [ (3)H]lazabemide binding to MAO-B in the lateral and basal nuclei of the amygdala and higher binding in the medial nucleus.
After midbrain raphe medial nucleus damage discharge activity of amygdalar nuclei markedly changes, mainly by reciprocal manner.
In contrast, rats that had received muscimol injections into their mPFC and were subsequently restrained exhibited an increase in the number of Fos-positive cells in the DMH, medial amygdala, and medial nucleus tractus solitarius as compared to vehicle-injected rats that experienced restraint stress.
The main sources of input to nucleus reuniens were from the orbitomedial, insular, ectorhinal, perirhinal, and retrosplenial cortices; CA1/subiculum of hippocampus; claustrum, tania tecta, lateral septum, substantia innominata, and medial and lateral preoptic nuclei of the basal forebrain; medial nucleus of amygdala; paraventricular and lateral geniculate nuclei of the thalamus; zona incerta; anterior, ventromedial, lateral, posterior, supramammillary, and dorsal premammillary nuclei of the hypothalamus; and ventral tegmental area, periaqueductal gray, medial and posterior pretectal nuclei, superior colliculus, precommissural/commissural nuclei, nucleus of the posterior commissure, parabrachial nucleus, laterodorsal and pedunculopontine tegmental nuclei, nucleus incertus, and dorsal and median raphe nuclei of the brainstem.
The medial nucleus and central extended amygdala also contain many well-differentiated bcl-2 positive cells.
medial nucleus accumbens core, central amygdala, lateral habenula) methamphetamine treatment were identified, thereby providing a comprehensive map of the short and long-term effects of methamphetamine on mouse brain activity per se.
The medial nucleus of the amygdala (MeA), a sexually dimorphic area, contains estrogen and androgen receptors and has an integrative role in behavioral, vegetative and endocrine activities of rats.
As a result, more Fos-LI neurons were observed in anterior cingulate cortex, retrosplenial cortex, insular cortex, parietal cortex area 2, frontal cortex area 1-3, claustrum, lateral septal area, amygdala, dorsomedial hypothalamic nucleus, central medial nucleus, paraventricular nucleus, superior colliculus, inferior colliculus and periaqueductal gray.
Our aim was to study the role of the olfactory amygdala (medial and cortical nuclei) and the ventromedial nucleus of the hypothalamus (VMN) in the ability of the male odour or live males to induce a release of luteinizing hormone in anoestrus ewes. In contrast, inactivation of part of the accessory olfactory system (the medial nucleus of the amygdala or the VMN) had no effect.
This was accomplished by visualizing stress-induced expression of Fos immunoreactivity in the paraventricular nucleus of the hypothalamus, lateral bed nucleus of the stria terminalis, central nucleus of the amygdala, and medial nucleus of the amygdala (MeA), as well as the noradrenergic nucleus locus coeruleus (LC).
By using in vivo micropush-pull superfusion and microdialysis techniques, we found a pronounced and long-lasting increase (150%) in SP release in the medial nucleus of the amygdala (MeA), but not in the central nucleus of the amygdala, in response to immobilization stress.
Mating behavior in male hamsters is regulated by a chemosensory pathway that converges on the bed nucleus of the stria terminalis (BST) and the medial nucleus of the amygdala (Me).
In contrast, significantly reduced spine densities were observed on the granule cell dendrites in the dentate gyrus (down to 92%) and on the apical dendrites in the medial nucleus of the amygdala (down to 95%).
Following lesions of the medial paralemniscal nucleus, TIP39-immunoreactive fibers disappeared from the medial geniculate body, the periaqueductal gray, the deep layers of the superior colliculus, the external cortex of the inferior colliculus, the cuneiform nucleus, the nuclei of the lateral lemniscus, the lateral parabrachial nucleus, the locus coeruleus, the subcoeruleus area, the medial nucleus of the trapezoid body, the periolivary nuclei, and the spinal cord, suggesting that these regions receive TIP39-containing fibers from the medial paralemniscal nucleus, and unilateral lesions demonstrated that the projections are ipsilateral.
Administration of typical and atypical antipsychotic drugs leads to activation of cells in the nucleus accumbens shell, central amygdaloid nucleus, and midline thalamic central medial nucleus, implicating important shared effects of these drugs. However, the exact cell types responding to antipsychotic drugs in the nucleus accumbens shell, central amygdaloid nucleus, and midline thalamic central medial nucleus are unclear. The present study provides pharmacological evidence, at the cellular level in vivo, that the shared effects of antipsychotic drugs, whether typical and atypical, is activation of dynorphinergic GABA neurons in the nucleus accumbens shell, central amygdaloid nucleus, and midline thalamic central medial nucleus.
An anxiogenic or a pharmacological stressor, N-methyl-beta-carboline-3-carboxamide (FG-7142), (20 mg/kg, intraperitoneally injected) induced a dense nuclear c-Fos-like immunoreactivity in the pyriform cortex, cingulate and retrosplenial cortex, layers II-VI of the neocortex, lateral habenula, lateral septum, paraventricular nucleus of the thalamus, striatum, central and medial nucleus of the amygdala, but a sparse c-Fos immunostaining in the hippocampus and layer I of the neocortex in the forebrain of 56-day-old rats. Among these regions, the 8-day-old rats expressed much fewer c-Fos-positive cells in the neocortex, lateral habenula, lateral septum and medial nucleus of the amygdala than the young adult rats following the FG-7142 injection.
Intracerebral microinjections of GLP-1 significantly suppressed food intake in the lateral (LH), dorsomedial (DMH), and ventromedial hypothalamus (VMH), but not in the medial nucleus of the amygdala.
The BSTp also sends a strong return projection to the medial nucleus of the amygdala.
There were moderate-to-heavy intra-amygdaloid projections terminating in the bed nucleus of the accessory olfactory tract, the central division of the medial nucleus, and the sulcal division of the periamygdaloid cortex.
Within the auditory system, the medial nucleus of the trapezoid had a robust signal consistent with staining of the giant presynaptic terminals.
After kainate administration, increased proN/OFQ gene expression was observed in the reticular nucleus of the thalamus and in the medial nucleus of the amygdala.
ERbeta mRNA levels exhibited significant correlations with ovarian steroid ratios (E2/P4) in various brain regions, including the bed nucleus of stria terminalis, the medial nucleus of amygdala, and the anteroventral periventricular nuclei but not the paraventricular and the supraoptic nuclei or the preoptic area of the hypothalamus.
In addition, increased BDNF immunoreactivity was found in fibers of many projection targets of the basolateral amygdala--the central extended amygdala, olfactory tubercle, medial nucleus accumbens, and in small zones resembling striosomes in the dorsal medial striatum.
In all three primates, DL/MT(C) had reciprocal connections with the pulvinar and claustrum; received afferents from the locus coeruleus, dorsal raphe, nucleus annularis, central superior nucleus, pontine reticular formation, lateral geniculate nucleus, paracentral nucleus, central medial nucleus, lateral hypothalamus, basal nucleus of the amygdala, and basal nucleus of Meynert/substantia innominata; and sent efferents to the pons, superior colliculus, reticular nucleus, caudate, and putamen.
The entorhinal projections were more evenly distributed between the medial nucleus accumbens and the olfactory tubercle, whereas the perirhinal projections were primarily to the olfactory tubercle.
Immunoreactive somata and processes are abundant in the amygdalo-hippocampal transition area, central nucleus, intra-amygdaloid bed nucleus of the stria terminalis, anterior and posterior cortical nuclei, periamygdaloid cortex and medial nucleus of the amygdala.
A striking sex difference in DORir was observed in the posterodorsal region of the medial nucleus of the amygdala, with males showing much greater DORir than females.
Serotonin release in the lateral hypothalamus, the central nucleus of amygdala and the medial nucleus raphe in overnight fluid-deprived rats during their first subsequent free drinking was also measured.
The medial nucleus of the amygdala (MeA) is a steroid-sensitive region that has been implicated in the expression of behaviors such as mating and aggression.
No double labeled cells were seen in medial preoptic area (MPOA), medial nucleus of the amygdala (Me), the bed nucleus of the stria terminalis (BNST), or the hypothalamus.
Within the shell, the dorsomedial region is distinguished by additional inputs from the medial nucleus.
In contrast, late-firing neurons were rare in the rat central nucleus and the cat central medial nucleus.
Lesions of the central nucleus impaired all three conditioned responses; lesions of the medial nucleus impaired conditioned modulation and avoidance.
Hypothalamic regions that were innervated prominently by Ucn III fibers included the ventromedial nucleus, medial preoptic nucleus, and ventral premammillary nucleus. Outside the hypothalamus, the densest projections were found in the intermediate part of the lateral septum, posterior division of the bed nucleus stria terminalis, and the medial nucleus of the amygdala.
The results of Experiment 1 suggest that olfactory and somatosensory inputs may functionally converge in the anterior region ot the medial nucleus (aMe).
Second, in contrast, the medial nucleus, and the rest of the amygdalar cell groups associated with the accessory and main olfactory systems innervate preferentially the posterior division, and the medial half of the anterior division, of the bed nuclei.
A signal for the short PDE4A1 isoform was found in regions in which the two long isoforms were both expressed, with the exception of the medial nucleus of the amygdala where weak signals for PDE4A5 and PDE4A10 were detected but PDE4A1 was absent.
Here we report that CB1 cannabinoid receptors are expressed at high levels in certain amygdala nuclei, especially in the lateral and basal nuclei, but are absent in other nuclei (e.g., in the central nucleus and in the medial nucleus).
No differences in NPY expression were found in the other regions analyzed: cingulate cortex, medial nucleus of the amygdala, arcuate, and paraventricular nuclei of the hypothalamus.
In the amygdala, haemorrhage and immune challenge both elicited c-fos expression in a large number of neurons in the central nucleus of the amygdala, whereas noise, restraint and forced swim primarily elicited recruitment of cells within the medial nucleus of the amygdala.
These pheromones also stimulate fos expression in neural areas that regulate copulation including: the medial nucleus of the amygdala, the bed nucleus of the stria terminalis, and the preoptic area. However, the accessory system plays the greater role in the regulation of mating behavior and has direct connections with the medial nucleus of the amygdala and bed nucleus of the stria terminalis.
These brain regions are all known to be involved in emotional behavior (anterior hypothalamus, medial nucleus of the amygdala, cingulate cortex) or autonomic regulation, respectively (solitary tract nucleus, dorsal motor nucleus of vagus).
These studies investigated whether the processing and retention of VCS involves acute glutamatergic activation or de novo protein synthesis within the medial nucleus of the amygdala (MEA), a VCS-responsive brain site that is implicated in P/PSP initiation.
The converse was true in the medial nucleus, where high concentrations of binding sites were associated with lower levels of DAMGO-stimulated G-protein activation. Finally, [ (3)H]DAMGO and [ (35)S]GTPgammaS binding within the amygdala, particularly the medial nucleus, formed a continuum with the substantia innominata and bed nucleus of the stria terminalis, supporting the concept of the extended amygdala in primates..
No particular pattern in cytochrome oxidase activity was detected in other amygdaloid sub-nuclei that were examined, including the basolateral and medial nucleus.
Senktide induced the highest number of FLI neurons in the lateral septum, bed nucleus of the stria terminalis, amygdala, paraventricular nucleus of the hypothalamus, median preoptic nucleus, organum vasculosum of the lamina terminalis, supraoptic nucleus, periaqueductal gray, and medial nucleus of the solitary tract compared to isotonic saline controls.
In WKY, restraint stress (1 day) induced significant decreases in GAL receptor density in forebrain regions such as the Ce (-41%) and medial nucleus of the amygdala (-41%) (P<0.05).
In the amygdala, OX1R mRNA was expressed throughout the amygdaloid complex with robust labeling in the medial nucleus, while OX2R mRNA was only present in the posterior cortical nucleus of amygdala.
FAE decreased 5-HTT binding sites in the medial nucleus of amygdala, dorsomedial and ventromedial nuclei of the hypothalamus. FAE decreased 5-HTT binding sites temporarily in the ventromedial nucleus of the hypothalamus in the 21-day-old female; this effect was found to disappear by day 40.
The other descending sympathetic pathway appears to target the medial preoptic nucleus as its key nodal point, receiving inputs from infralimbic cortex and limbic regions, such as the lateral septum, medial nucleus of the amygdala, subiculum, and amygdalohippocampal area, and then, projecting caudally to the hypothalamus and brainstem.
This effect is generally held to depend upon the central nucleus of the amygdala, but recent evidence suggests a role for the medial nucleus.
Additionally, a diffuse projection with small varicosities spreads in the area between the two VPpc nuclei and the central medial nucleus.
This chapter focuses on the parvicellular vasopressin (VP) system originating from the medial nucleus of the amygdala (MeA) and bed nucleus of the stria terminalis (BNST).
Yet, the lateral nucleus does not project to the central medial nucleus, where most brainstem projections of the amygdala originate. The available evidence suggests that the basal nuclei could transmit information from the lateral to the central medial nucleus. However, interposed between the basolateral complex and the central nucleus are clusters of GABAergic cells, the intercalated neurons, which receive inputs from the lateral and basal nuclei and contribute a massive projection to the central medial nucleus.
In somewhat lower amounts, stained cells could be found in several nuclei of the amygdala (in the basomedial, basolateral, lateral, central and medial nucleus of the amygdala, in the amygdalopiriform transition area and in the amygdalohippocampal transition area as well as in the bed nucleus of the stria terminalis)..
After chronic (2 weeks) HPD treatment, acute administration of HPD decreased signal intensity in the caudate-putamen at 60 min, in the hypothalamus at 30 min, the perirhinal cortex from 2 to 120 min, the dorsomedial and ventral posterior nuclei of the thalamus from 2 to 120 min, and the medial nucleus of the amygdala from 60 to 120 min.
Although Fos was induced by mating in several regions, this response was only dimorphic in the ventral medial nucleus of the hypothalamus (VMN), where mating significantly increased Fos-ir in females, but not in males.
For example, prenatal fluoxetine exposure significantly altered the density of 5-HT transporters in subregions of the hypothalamus (dorsomedial nucleus, -21%; lateral hypothalamus, +21%), hippocampus (CA2, +47%; CA3, +38%), and amygdala (basolateral nucleus, +32%; medial nucleus, +44%) in prepubescent offspring.
This experiment examined whether testosterone proprionate (T) action in the medial preoptic area (MPO) would synergize with T action in the medial nucleus of the amygdala (AME) for the expression of androgen-dependent behaviors in house mice.
The major projections from the ventral division are directed to the parvicellular division of the basal nucleus, the parvicellular division of the accessory basal nucleus, the medial nucleus, and the periamygdaloid cortex.
Horizontal slices containing some nuclei of the amygdala (lateral nucleus, basolateral nucleus, central nucleus, medial nucleus), as well as the entorhinal cortex, the hippocampus and parts of the piriform cortex were used.
The c-fos mRNA was increased in the medial nucleus of the amygdala in all of the groups that were placed in the test chamber. However, after the retention test, the expression of c-fos mRNA in the medial nucleus of the amygdala did not differ between groups.
The effects of long and short photoperiod (LP; SP) exposure on steroid receptor immunoreactivity were examined in the ventromedial hypothalamus (VMH), medial tuberal region (mTu), medial preoptic area (mPOA), medial nucleus of the amygdala (mAMYG), and the arcuate nucleus (ARC) of ovariectomized hamsters.
Sparse alpha-melanocyte-stimulating hormone-immunoreactive fibers were found in the basomedial nucleus of the amygdala, whereas a low density of fibers containing alpha-neo-endorphin was observed in the anterior amygdaloid area. A moderate density was observed in the basomedial nucleus and in the medial and cortical nuclei. Fibers containing somatostatin-28 (fragment 1-12) were observed in all the amygdaloid nuclei, whereas immunoreactive cell bodies were found in all the nuclei except in the medial part of the central nucleus and the medial nucleus.
Moderate or low concentrations of phenyletanolamine-N-methyltransferase-immunopositive fibres are present in the paratenial nucleus, and all parts of the central nucleus, nucleus reuniens, central medial nucleus, centromedian nucleus, medial geniculate body and medial pulvinar nucleus, while only scattered immunoreactive axons are found in other thalamic nuclei.
Based upon similarities in sex-steroid binding sites, this nucleus has been hypothesized to be homologous to the medial nucleus of the amygdala (Me) in mammals, which is known to modulate the expression of sexual behavior in rodents.
Double labeled neurons by NADPH-diaphorase and CTb were also identified mostly in the medial nucleus. Approximately 40% of the neurons projecting to the PVN were nitrergic neurons and 16% of NADPH-diaphorase positive neurons in the medial nucleus were revealed to project to the PVN.
Injections involving the accessory olfactory bulb and AON produced additional labeling of cells within the bed nucleus of the stria terminalis (BNST), medial nucleus of the amygdala, and a few cells in the posteromedial cortical nucleus of the amygdala.
Labelled neurons were also found in limbic system structures such as the bed nucleus of stria terminalis (BST) and the medial nucleus of the amygdala, in a few thalamic nuclei, and in the central gray. The levels of L-PRL mRNA were higher in females on day 21 of pregnancy in the MPO and in the choroid plexus, than in females on day 2 of pregnancy; levels in the ventromedial nucleus of the hypothalamus (VMH) were unchanged across pregnancy.
We observed an increase in mu-opioid receptor mRNA levels in the ventromedial nucleus of the hypothalamus (VMH) and arcuate nucleus (ARN) after 48 h of 10 microg of 17-beta-estradiol-3-benzoate treatment when compared to OVX females. No effects of estrogen were observed on mu-opioid receptor mRNA levels in the posterior medial nucleus of the amygdala (MeAmyg), hippocampus, caudate-putamen (CPu) or the medial habenula.
Numerous CB-positive neurons were observed in all subdivisions of the medial nucleus. The posterodorsal subdivision of the medial nucleus exhibited a centrally located island of small CB-negative neurons and three cell-dense clusters of CB-positive neurons.
The damage of the medial nucleus decreases animals' primordial pain reactivity. Four minutes of continuous foot-shock produced post-stress analgesia in all control and lesioned rats, but 20 min of regularly intermittent foot-shock failed to evoke analgesia in the lesioned rats, especially in subjects with the dorsal part of the medial nucleus injuries.
This study was designed to investigate the effects of pheromonal cues and specific behaviors within the male copulatory sequence on c-fos expression in the medial nucleus of the amygdala (Me), the bed nucleus of the stria terminalis (BNST), and the medial preoptic area (MPOA) of the Syrian hamster brain.
The medial nucleus of the pulvinar complex (PM) has widespread connections with association cortex.
Mating behavior in male hamsters is initiated by pheromones, detected by two chemosensory systems which converge on the medial nucleus of the amygdala and the bed nucleus of the stria terminalis.
Using Fos as a marker of neuronal stimulation we have found that (1) FHVS stimulates neurons in the posterior subdivision of the medial nucleus of the amygdala (MeP), the posterior medial subdivision of the bed nucleus of the stria terminalis (BNSTpm), and the magnocellular subdivision of the medial preoptic nucleus (MPN mag); (2) this stimulation is mediated by the main olfactory system; (3) stimulation of the MPN mag is regulated by testosterone in males; (4) stimulation of the BNSTpm and MeP is regulated by testosterone in females; and (5) FHVS does not induce Fos production in the MPN mag in females regardless of the hormonal state.
In this study we analyzed potential estrogen effects on the oxytocin receptor mRNA levels in some areas integral to the limbic-hypothalamic system, namely the ventromedial nucleus of the hypothalamus (VMH), posterior medial nucleus of amygdala (MeAmyg), and arcuate nucleus (ARC), as well as the caudate putamen (CPu), CA1 region of the hippocampus, anterior pituitary, and uterine tissue of ovariectomized (OVX) female rats.
The lesions were fairly well restricted to the rostral half of the central nucleus (rACe), or the cholinergically richly innervated basolateral nucleus (ABL) or the medial nucleus (AMe) of the amygdala.
Exposure to the pheromones in FHVS (female hamster vaginal secretions) induces Fos immunoreactivity (Fos-IR) in the posterior subdivision of the medial nucleus of the amygdala (MeP) and the posteromedial subdivision of the bed nucleus of the stria terminalis (BNSTpm) of both sexes and stimulates the magnocellular subdivision of the medial preoptic nucleus (MPNmag) in males but not in females.
PPE mRNA levels were also increased at 24 and 48 h after estrogen treatment in the posterior medial nucleus of the amygdala (MeAmyg) by 3.3- and 2.5-fold, respectively, and in the arcuate nucleus (ARC) by 2- and 1.9-fold, respectively.
The major intra-amygdaloid projections from the accessory basal nucleus were directed to the medial and capsular divisions of the central nucleus, the medial division of the amygdalohippocampal area, the medial division of the lateral nucleus, the central division of the medial nucleus, and the posterior cortical nucleus.
For example, the prelimbic cortex projects to the medial nucleus accumbens, and receives input from the paraventricular thalamic nucleus and the parvicellular basal amygdala. These latter two areas also project to the medial nucleus accumbens.
Hamsters underwent sham surgery (SH), bilateral BX, or electrolytic or radiofrequency lesions of the: medial nucleus of the amygdala (MeX) caudal LOT just rostral to the medial nucleus of the amygdala (LOTX); or ventral striatum (VSX).
The paralaminar nucleus, central nucleus, medial nucleus, and the periamygdaloid cortex contained the lowest densities of calretinin neurons.
In rodents, reproductively relevant pheromonal cues are detected by receptors in the vomeronasal organ, which in turn transmit this information centrally via the accessory olfactory bulb, the medial nucleus of the amygdala, the posterior medial bed nucleus of the stria terminalis and the medial preoptic area. Chemosensory stimulation failed to augment Fos immunoreactivity in neurons located in the ventrolateral subregion of the ventromedial nucleus of the hypothalamus or in the midbrain central tegmental field, sites at which mating has previously been shown to augment Fos immunoreactivity in both sexes.
The avoidance test and elevated plus maze induced prominent Fos-LI in select brain regions, including the medial prefrontal, cingulate, and ventrolateral orbital cortices, taenia tecta, nucleus accumbens, paraventricular nucleus of the hypothalamus, medial nucleus of the amygdala and lateral septum. Air puff stimuli that produced ultrasonic vocalizations induced Fos-LI to a more limited extent compared to the plus maze and avoidance test, with only the medial prefrontal cortex, medial nucleus of the amygdala, and lateral septum being significantly affected by air-puff.
Tissue samples were taken from 12 brain nuclei: lateral septum, bed nucleus of the stria terminalis, medial preoptic nucleus, anterior hypothalamic area, arcuate nucleus, corticomedial nucleus of the amygdala, lateral preoptic area, parietal cortex, medial nucleus of the amygdala, dorsomedial nucleus of the hypothalamus, ventromedial nucleus of the hypothalamus, and dorsal hippocampus.
The lateral division of the central nucleus also stains intensely, whereas the medial division of the central nucleus and the medial nucleus are more weakly stained.
The medial nucleus of the amygdala (Me), bed nucleus of the stria terminalis (BNST), and medial preoptic area (MPOA) regulate copulation in the male hamster.
These correlate well with the cytoarchitectonically defined nuclei of the PB complex and with the pattern of ascending axons from the medial nucleus of the solitary tract and the area postrema terminating in the PB.
The available evidence suggests that the lateral nucleus is the input station of the amygdala for auditory conditioned stimuli, whereas the central medial nucleus is the output for conditioned fear responses. The present study was undertaken to determine if the main intra-amygdaloid targets of the lateral nucleus, namely the basomedial and basolateral nuclei, project to the central medial nucleus. To rule out the possibility that the anterograde labeling reflected passing fibers merging with the major fiber bundles that course in and around the central medial nucleus, labeled terminals and varicosities were observed in the electron microscope. They both project to the central medial nucleus, nucleus of the lateral olfactory tract and peri-amygdaloid cortex, but have limited projections to each other. Small Phaseolus vulgaris-leucoagglutinin injections in both nuclei gave rise to prominent intranuclear projections but only the basomedial nucleus was found to project to the lateral and anterior cortical nuclei. This is the first unambiguous demonstration that the basolateral and basomedial nuclei project to the central medial nucleus. Since these nuclei constitute the main intra-amygdaloid targets of the lateral nucleus, they represent likely candidates for the transmission of auditory conditioned stimuli to the central medial nucleus in auditory fear conditioning..
In the rat, fibers from the prelimbic cortex terminate in the medial nucleus accumbens. Anterior paraventricular thalamic and parvicellular basal amygdaloid fibers reached both the prelimbic cortex and the medial nucleus accumbens.
None of the treatments affected CRH-R mRNA levels in the central and medial nucleus of the amygdala or the BNST.
However, dorsal regions of the ventral division provide rather dense inputs to the medial preoptic region and capsule of the ventromedial nucleus, whereas ventral regions of the ventral division preferentially innervate the anterior hypothalamic, dorsomedial, and ventral parts of the ventromedial nuclei.
The regions containing the lowest density of parvalbumin-immunoreactive cells were the paralaminar nucleus, the parvicellular division of the basal nucleus, the central nucleus, the medial nucleus and the anterior cortical nucleus.
The present study examined single neuron activity in the medial nucleus of the medial geniculate (mMG) and amygdaloid central nucleus (ACe) simultaneously across several phases of differential heart rate conditioning (habituation, acquisition, and extinction).
In contrast, although mating and agonistic behavior both activated neurons within the caudal subdivision of the medial nucleus of the amygdala, the anterodorsal level of posteromedial bed nucleus of the stria terminalis and the paraventricular and ventromedial nuclei of the hypothalamus, in these areas either the distribution and/or number of Fos-immunoreactive neurons differed.
The major extranuclear projections of the lateral nucleus are (in descending order of magnitude) to the accessory basal nucleus, the basal nucleus, the periamygdaloid cortex, the dorsal portion of the central division of the medial nucleus, the posterior cortical nucleus, the capsular division of the central nucleus, and the lateral division of the amygdalohippocampal area.
They were detected in the striatal cell bridges, the olfactory tubercle, the principal nucleus of the bed nucleus of the stria terminalis and the medial nucleus of the amygdala of the telencephalon and in the medial preoptic, the ventromedial and the ventral premammillary nuclei of the hypothalamus.
By days 5-6 virus had spread to the contralateral medial nucleus of the medial geniculate complex, posterior thalamus, and ventroposteromedial thalamus.
The dense immunostaining in the medial nucleus accumbens was directly continuous with dense secretoneurin immunoreactivity in the bed nucleus of the stria terminalis.
Very few labeled cell bodies were seen in the anterior amygdaloid area and the medial nucleus. Finally, in the basomedial nucleus, very few labeled cell bodies were present in the rostral two-thirds, whilst a considerable number was encountered in the caudal one-third.
No significant effect is found in the following areas: forebrain: nucleus accumbens, striatum, and medial septum; hypothalamus: lateral, ventro-medial, dorso-medial, and posterior nuclei; thalamus: centro-medial nucleus, lateral part of the zona incerta, and lateral geniculate body; hippocampus: dorsal and ventral parts; midbrain: central tegmentum, ventral tegmental area, and substantia nigra.
The second facilitatory pathway arises from the medial nucleus of the amygdala.
These include the medial nucleus, basal complex and central nucleus of the amygdala. Experiments involving dual stimulation of an amygdaloid nucleus and sites within the medial hypothalamus or PAG from which defensive rage behavior was elicited demonstrated that two of the regions facilitated defensive rage --the medial nucleus and basal complex--and a third region--the central nucleus--suppressed defensive rage.
Axon-sparing lesions of the medial nucleus of the amygdala (MeA) decrease male parental behavior in the highly social prairie vole.
To determine if TCDD exposure had an effect specific to sexual differentiation of the brain, estrogen receptor concentrations in the medial preoptic nucleus (MPO), ventrolateral aspect of the ventro-medial nucleus, and periventricular preoptic area were assessed.
Medial cuts also labeled more cells in the ventral part of the lateral septal nucleus, the encapsulated part of the bed nucleus of the stria terminalis, the medial nucleus of the amygdala, the amygdalohippocampal area, and the ventral premammillary nucleus than lateral cuts did.
When microinjected into the medial, central, basolateral, and posterior lateral nuclei of the amygdala complex (AC), both CCh and oxotremorine produced a significant increase in the TFL, but in no case was the effect stronger than that produced by stimulation of the medial nucleus. When microinjected into the same nuclei of the AC, CCh, but not oxotremorine, produced behavioral changes which were less frequent after stimulation of the medial nucleus. The behavioral changes, but not the antinociception, produced by CCh microinjected into the medial nucleus were inhibited by diazepam (1 mg/kg, i.p.
In a second study, NMA lesions restricted to the medial nucleus also decreased paternal behavior. Neurons in the medial nucleus of the amygdala appear to be essential for the normal expression of paternal care in this species..
The medial nucleus and the central nucleus displayed a low density of nerve growth factor receptor-positive fibers.
The core projects mainly to itself and to the basomedial nucleus, whereas the shell contributes a massive projection to the basolateral nucleus. No projection of the lateral nucleus to the central medial nucleus was found. Since most amygdaloid projections to the brainstem originate in the central medial nucleus, these results suggest that intra-amygdaloid targets of the lateral nucleus are involved in the transmission of auditory conditioned stimuli to the central medial nucleus.
The ventromedial nucleus of the hypothalamus (VMH) plays a crucial role in the mediation of lordosis by integrating predominantly inhibitory limbic signals with cyclic variation of ovarian steroids and sending a stimulatory output to the midbrain, especially the periaqueductal gray (PAG). We have used a combination of retrograde tracers to map VMH projections to the medial division of the medial preoptic nucleus (MPNm), posterodorsal division of the medial nucleus of the amygdala (MeApd), and the PAG.
CCK mRNA-positive neurons in normal rats were seen throughout the amygdaloid complex, with the most heavily labeled neurons in lateral, basal, and cortical nuclei, followed by the medial nucleus.
Our previous reports of major sex differences in the substance P-immunoreactive (SPir) innervation of the medial posterior divisions of the bed nucleus of the stria terminalis (BST) and medial nucleus of the amygdala in rats raised the question of the hormonal regulation of this innervation.
The data provide support for the view that a lesion in the anterior thalamus can produce amnesia if it compromises the hippocampal pathway and either the amygdalar pathway or that arising from the perirhinal cortex and terminating in the dorso-medial nucleus of the thalamus.
The positive correlation between the number of fos-positive cells in the posterodorsal medial amygdala (PDMA) and the increase in LQ and that between the number of fos-positive cells in the PDMA and the percentage of fos-positive LHRH cells were significant, supporting the role of the medial nucleus of amygdala in lordosis.
The non-CAnergic brain regions that represented CAT-stained cells were further divided into two groups: (i) regions containing AADC-labeled cells, for example, bed nucleus of the stria terminalis, nucleus suprachiasmaticus, mammillary body, nucleus raphe dorsalis, inferior colliculus, and nucleus parabrachialis, and (ii) regions containing no AADC-positive cells, for example, main olfactory bulb (except A16), accessory olfactory bulb, nucleus olfactorius anterior, caudoputamen, septum, nucleus accumbens, hippocampus, medial nucleus of the amygdala, entorhinal cortex, nucleus supraopticus, and parasubiculum.
Most intercalated neurons projecting to the medial nucleus were found in the larger, rostrally located intercalated cell masses.
The present study was designed to test the hypothesis that a major excitatory mechanism for the expression of feline defensive rage behavior involves the medial nucleus of the amygdala which utilizes substance P as a neurotransmitter in a direct output pathway that supplies the medial hypothalamus. The data indicated that large numbers of retrogradely and immunocytochemically positive labeled cells were identified in the medial nucleus, including many that were double-labeled.(ABSTRACT TRUNCATED AT 400 WORDS).
The lateral nucleus displayed a relatively low density of cholinergic innervation, and there were only rare ChAT-positive fibers in the medial nucleus.
The effect of bilateral lesion of the medial nucleus of amygdala (mAMY) on the mating-induced enhancement of lordosis behavior in ovariectomized (OVX) estrogen-primed rats was investigated.
The results of the present study indicate that exposure to vaginal secretions from a female Syrian hamster (FHVS) stimulates c-fos production in the medial nucleus of the amygdala (Me), the bed nucleus of the stria terminalis (BNST) and the medial preoptic area (MPOA).
Cholecystokinin (CCK) is colocalised with dopamine in the postero-medial nucleus accumbens (NAS).
Nuclear AR levels, on the other hand, were significantly elevated after T treatment (activated) only in the ventral medial nucleus (VMN) and infundibular nucleus/median eminence (P < 0.05).
The medial nucleus of the amygdala, bed nucleus of the stria terminalis and medial preoptic area play critical roles in the regulation of mating behavior in the male hamster. In this study we report 1) that a closely related peptide, NKA (substance K), is also present in the medial nucleus of the amygdala, the bed nucleus of the stria terminalis and the medial preoptic area; 2) that all those neurons which contain SP also contain NKA and 3) testosterone also regulates the production of NKA.
The regions containing the lowest densities of parvalbumin-positive profiles were the medial nucleus, anterior cortical nucleus, central nucleus, and the paralaminar nucleus.
ITC and ITR receive afferents from the locus coeruleus, dorsal raphe, nucleus annularis, central superior nucleus, pontine reticular formation, lateral hypothalamus, paracentral nucleus, and central medial nucleus; send efferents to the superior colliculus, reticular nucleus, and striatum; and have both afferent and efferent connections with the pretectum, pulvinar, claustrum, amygdala, and basal nucleus of Meynert.
There were numerous GABA-positive neurons in the lateral subdivision of the central nucleus and fewer cells in the medial nucleus and medial subdivision of the central nucleus.
These structures were the solitary tract nucleus, the dorsal motor nucleus of the vagus, the periaqueductal gray, the perifornical region of the hypothalamus and the medial nucleus of the amygdala. In 3 nuclei, the solitary tract nucleus, the periaqueductal gray and the medial nucleus of the amygdala, dominants had significantly higher Kd-values than subordinates.
The second large pathway ascends through the medial zone of the hypothalamus and densely innervates the ventrolateral part of the ventromedial nucleus and adjacent basal parts of the lateral hypothalamic area, medial preoptic nucleus, principal nucleus of the bed nuclei of the stria terminalis, ventral lateral septal nucleus, posterodorsal part of the medial nucleus of the amygdala, posterior nucleus, and immediately adjacent regions of the posterior cortical nucleus of the amygdala. Relatively sparse terminal fields associated with ascending fibers were also observed in the dorsomedial nucleus of the hypothalamus; in the nucleus reuniens, parataenial nucleus, paraventricular nucleus of the thalamus, and mediodorsal nucleus; in the central nucleus of the amygdala, anterodorsal part of the medial nucleus of the amygdala, posterior part of the basomedial nucleus of the amygdala; and in the ventral subiculum and adjacent parts of hippocampal field CA1, and the infralimbic and prelimbic areas of the medial prefrontal cortex.
This region, called here the posterior nucleus of the amygdala (PA), corresponds in part to an area that has been referred to as the cortico-amygdaloid transition area, posterior part of the medial nucleus of the amygdala, amygdalo-hippocampal transition area, and posteromedial basal nucleus. Experiments with fluorogold and phaseolus vulgaris leucoagglutinin (PHAL) indicate that the major neuronal input to the PA arises in the ventral premammillary nucleus, and that substantial projections also arise in olfactory-related areas such as the medial nucleus of the amygdala, bed nucleus of the accessory olfactory tract, and posterior cortical nucleus of the amygdala, as well as in the ventral subiculum and adjacent parts of hippocampal field CA1. The efferent projections of the PA as determined with the PHAL method appear to follow five major routes: 1) a relatively small group of laterally directed fibers innervates the dorsal endopiriform nucleus, and a few of these fibers reach cortical area TR and the lateral entorhinal area; 2) another small group of fibers courses medially to innervate the ventral subiculum and adjacent parts of field CA1; 3) many fibers course ventrally to innervate the outer molecular layer of the medial part of the posterior cortical nucleus of the amygdala; 4) a moderate group of fibers courses rostrally to innervate primarily the posterodorsal part of the medial nucleus of the amygdala, although some fibers continue on to end less densely in rostral parts of the medial nucleus of the amygdala before leaving the amygdala through the ansa peduncularis; and 5) the major output of the PA courses through the stria terminalis. One branch of this pathway massively innervates the principal nucleus of the bed nuclei of the stria terminalis before entering the medial hypothalamus, where it ends massively in the anteroventral periventricular and medial preoptic nuclei, ventrolateral part of the ventromedial nucleus and adjacent parts of the basal lateral hypothalamic area, and ventral premammillary nucleus.
Gonadal steroids may regulate mating behavior by actions on the medial nucleus of the amygdala, bed nucleus of the stria terminalis, and medial preoptic area. Bilateral enucleation caused a decrease in the number of substance P neurons in the medial nucleus, bed nucleus of the stria terminalis, and medial preoptic area (P less than 0.05). Thus, a decrease in daylength causes a decrease in substance P in the medial nucleus of the amygdala, the medial bed nucleus of the stria terminalis and the medial preoptic area that is mediated by changes in testosterone levels..
The medial nucleus of the amygdala, bed nucleus of the stria terminalis, and medial preoptic area appear to mediate steroidal regulation of mating behavior in male rodents. Brains from male Syrian hamsters that were (1) gonadally intact, (2) castrated for 13 weeks, or (3) castrated for 9 weeks and treated with testosterone for 4 weeks, were processed for substance P, and the numbers of substance P immunoreactive neurons in the medial nucleus of the amygdala, bed nucleus of the stria terminalis, and medial preoptic area were determined. Castration did not reduce the number of substance P neurons in the medial nucleus of the amygdala; however, testosterone treatment increased the numbers of these neurons when compared to intacts. As substance P enhances male copulatory behavior our results suggest that testosterone may regulate copulatory behavior by enhancing substance P levels in medial nucleus of the amygdala, bed nucleus of the stria terminalis and medial preoptic area..
Moderately dense plexuses of CRF-positive fibers also were seen in layer Ia of the periamygdaloid cortex, nucleus of the lateral olfactory tract, anterior and posterior cortical nuclei, and the medial nucleus.
The volume of the posterodorsal region of the medial nucleus of the amygdala (MApd) is approximately 85% greater and the volume of the encapsulated region of the bed nucleus of the stria terminalis (BNSTenc) is approximately 97% greater in males than in females.
Within the subnuclei of the amygdala, immunoreactive neuritic elements were most dense within the central nucleus followed by the medial nucleus and intercalated nuclei.
The medial nucleus of the amygdala is important for the neural control of reproductive behavior in the adult male Syrian hamster. Two types of signals are essential for this behavior, chemosensory stimuli and gonadal steroids; these signals appear to be received in different parts of the medial nucleus. In this study, the efferent projections of the anterior and posterior divisions of the medial nucleus of the amygdala in the Syrian hamster were analyzed throughout the forebrain after injections of the anterograde neuronal tracer, Phaseolus vulgaris-leucoagglutinin. Neurons of the anterior, but not the posterior, medial nucleus, were found to project to numerous olfactory bulb projection areas and to the ventral striatopallidal complex. Within areas of the chemosensory circuitry that control reproductive behavior, the anterior region of the medial nucleus projects to the intermediate part of the posterior bed nucleus of the stria terminalis and the lateral part of the medial preoptic area, whereas the posterior region of the medial nucleus projects to the medial parts of these areas. Differences in targets were also observed in the ventromedial nucleus of the hypothalamus where the anterior region projects to the core while the posterior part projects to the shell of this nucleus. Furthermore, reciprocal projections between the anterior and posterior regions of the medial nucleus were observed.
The medial nucleus of the amygdala (Me) processes both chemosensory and hormonal input. These results suggest that in orchidectomized male Syrian hamsters, testosterone or its aromatized form, estradiol, but not dihydrotestosterone, is sufficient to maintain the normal morphology of the neurons in the posterior part of the medial nucleus of the amygdala..
In addition to the neuronal and fiber staining, a diffuse, blue neuropil staining was also observed, most commonly in the anterior cortical nucleus, the medial nucleus, the intercalated nuclei, and especially in the amygdalohippocampal area.
No strain differences were evident in the medial nucleus of the amygdala, the bed nucleus of the stria terminalis, the median eminence, the anterior hypothalamic nucleus, or the hypothalamic dorsomedial nucleus..
This projection was topographically organized: rostral thalamic deposits elicited labelling in the medial caudate nucleus and the medial nucleus accumbens.
To determine if substance P- or prodynorphin-containing neurons of the medial nucleus of the amygdala and medial bed nucleus of the stria terminalis send projections to the medial preoptic area in the male Syrian hamster, we placed a fluorescent retrograde tract tracer (either Fluoro-gold, or rhodamine- or fluorescein-impregnated latex microspheres) into the medial preoptic area. Retrogradely labeled cell bodies were also observed in the posterodorsal subdivision of the medial nucleus of the amygdala.
These labeled structures included the central nucleus of the amygdala; the entopeduncular nucleus; the globus pallidus; the reticular and ventral lateral geniculate nuclei of the thalamus; parts of the hypothalamus including the dorsal, lateral, and posterior hypothalamic areas and the ventromedial and parvicellular nuclei; the zona incerta and fields of Forel; parts of the substantia nigra including the pars reticularis and pars lateralis, and the retrorubral area; the pretectum; the intermediate and deep layers of the superior colliculus; the periaqueductal gray; the dorsal nucleus of the raphe; portions of the reticular formation, including the mesencephalic, pontis oralis, pontis caudalis, gigantocellularis, ventralis, and lateralis reticular nuclei; the nucleus cuneiformis; the marginal nucleus of the brachium conjunctivum; the locus coeruleus; portions of the trigeminal complex, including the principal sensory and spinal nuclei; portions of the vestibular complex, including the lateral division of the superior nucleus and the medial nucleus; deep cerebellar nuclei, including the medial and lateral cerebellar nuclei; and lamina VII of the cervical spinal cord.
NE levels in the medial nucleus of the amygdala (MA), medial preoptic area (MPOA), ventromedial nucleus of hypothalamus (VMH) and bed nucleus of stria terminalis (BST) were measured.
Highest labelling was seen in the periventricular nucleus of the hypothalamus followed by telencephalic regions such as cortex, hippocampus and the medial nucleus of the amygdala.
The results indicate that: (1) the IVA receives a wide variety of telencephalic inputs, not only from visual, sensorimotor, auditory, limbic and association cortical areas, and from the claustrum, amygdala and basal nucleus of Meynert, as well, but also from the diencephalic projections arising mainly from the lateralis medialis-suprage niculate nuclear complex (LM-Sg) and the ventral medial nucleus (VM).
The principal striatal projection of the caudal basolateral nucleus was to the medial nucleus accumbens. Amygdaloid labeling produced by injections into the medial nucleus accumbens was very similar to that seen with injections into the lateral portions of the bed nucleus of the stria terminalis and central amygdaloid nucleus.
Inhibition of PV was induced by lateral parts of the medial principal nucleus, medial nucleus, central nucleus and a part of the pericortical nucleus.
After injections of retrograde tracer into the CeA, retrogradely labeled neurons were observed within the caudal, medial nucleus of the solitary tract. Most CeA-projecting neurons were located ipsilaterally within the medial nucleus of the solitary tract at the level of the area postrema. Retrogradely labeled enkephalin- and neurotensin-immunoreactive neurons were found within the medial nucleus of the solitary tract at this level, while retrogradely labeled neuropeptide Y-immunoreactive neurons were found within the medial nucleus of the solitary tract rostral to the area postrema.
In rat brain, AR was present in the medial preoptic, arcurate, and ventromedial nuclei of the hypothalamus, the medial nucleus of the amygdala, the CA-1 hippocampus, and the cortex.
Midline thalamo-hippocampal cells are concentrated in the nucleus reuniens; thalamo-accumbens neurons prevail in the ventral portion of the paraventricular nucleus, and in the central medial nucleus.
Most projections arose from areas overlying the dorsal motor nucleus, mainly the medial nucleus. Most dynorphin and neuropeptide Y immunoreactive projection cells were found rostral to that of enkephalinergic and somatostatinergic projections, and mainly in the ipsilateral medial nucleus.
laterobasal nucleus) have, in general, relatively few neuritic plaques; and (3) nuclei which receive olfactory projections are not uniformly affected, the cortical nucleus being heavily affected but the medial nucleus consistently spared..
Discrete fields of substance P-immunoreactive fibers are present within the posterior dorsal division of the medial nucleus of the amygdala and the posterior medial bed nucleus of the stria terminalis in adult male and female rats.
The greatest number of SOM-NPY double-labeled cells was observed in the medial nucleus, lateral nucleus, and intra-amygdaloid portion of the bed nucleus of the stria terminalis.
In addition, the medial preoptic area, bed nucleus of the stria terminalis, and medial nucleus of the amygdala stain lightly for prodynorphin-containing fibers and cells in the rat, compared to heavy cell and fiber staining in the hamster in all three of these regions.
Sparse to moderate axonal and terminal labeling was observed within the magnocellular parts of the paraventricular nucleus in animals that had injections of tracer into either the medial central nucleus or the medial nucleus. The medial nucleus innervates the rostral parvocellular parts of the paraventricular nucleus.
To determine the extent of colocalization of substance P (SP) and prodynorphin peptides within neurons of the medial nucleus of the amygdala (AMe), medial bed nucleus of the stria terminalis (BNSTm) and medial preoptic area (MPOA), we incubated colchicine-treated Syrian hamster brain tissue in an antiserum mixture containing rat anti-SP antibody combined with 1 of 3 rabbit antibodies against prodynorphin peptides: anti-dynorphin A(1-17), anti-dynorphin B(1-13) or anti-C-peptide.
Significant increases in the hexokinase reaction product were seen in the parvocellular component of the paraventricular nucleus of the hypothalamus, the supraoptic nucleus, the arcuate nucleus, the subfornical organ, the median preoptic nucleus, and the medial nucleus of the amygdala in both the 3-day and 13-day tARN animals.
The highest densities of labeled neurons were observed in layer III of the periamygdaloid cortex, in layers II and III of the medial nucleus, in the magnocellular division of the accessory basal nucleus, and in the medial portion of the lateral nucleus. Highest densities of immunoreactive fibers were observed in the periamygdaloid cortex, medial nucleus, parvicellular division of the accessory basal nucleus, paralaminar nucleus, ventrolateral portion of the lateral nucleus, parvicellular division of the basal nucleus, and the lateral division of the central nucleus.
The posterodorsal part of the medial nucleus of the amygdala (MeAp) receives its major sensory input from the accessory olfactory bulb and projects massively to the medial preoptic nucleus and other sexually dimorphic hypothalamic nuclei thought to play key roles in mediating steroid-sensitive reproductive functions.
Inhibition of PV (bladder relaxation) was induced from the medial nucleus, the central nucleus, lateral parts of the medial principal nucleus and parts of the pericortical nucleus.
3) The central and medial nucleus seem to be the main target of GABAergic fibers to the amygdala.
Fiber projections extended rostrally to and/or through the anterior hypothalamus, preoptic area, nucleus accumbens, septum, diagonal bands of Broca, caudate-putamen, frontal cortex and accessory olfactory bulb; laterally to the amygdala, especially the central nucleus and some parts of the medial nucleus; caudally to and/or through the midbrain central gray, reticular formation, parabrachial region, and several portions of the lower brain stem and spinal cord extending to sacral levels.
By infusing lignocaine locally into the accessory olfactory bulb and second order olfactory synapses in the medial nucleus of the amygdala, this study localizes changes that occur in the accessory olfactory bulb at mating to be subsequently important in preventing the stud male's pheromones from blocking pregnancy.
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