Ventral Raphe

Additionally, outside of the hypothalamus, labeling was observed in the thalamic parafascicular nucleus, the Edinger-Westphal nucleus, locus coeruleus, ventral raphe system, nucleus of solitary tract and in the preganglionic sympathetic intermediolateral cell column of the spinal cord, and the pituitary anterior and intermediate lobes.  

Furthermore, there were projections into the reticular formation of the lateral and dorsocaudal medulla and lateral pons, into nucleus gracilis, inferior and medial vestibular nuclei, lateral reticular nucleus, ventral raphe, pontine gray, superior colliculus, PAG and mediodorsal thalamic nucleus.  

Subcortical moderate to weak projections reach the PAG from the central and medial amygdala, nucleus of the stria terminalis, septum, nucleus accumbens, lateral preoptic region, lateral and posterior hypothalamus, globus pallidus, pretectal area, deep layers of the superior colliculus, the pericentral inferior colliculus, mesencephalic trigeminal nucleus, locus coeruleus, substantia nigra pars compacta, dorsal and ventral raphe, vestibular nuclei, spinal trigeminal nucleus, solitary tract nucleus, and nucleus gracilis.  

Using focal electrical stimulation at different dorsoventral raphe/parapyramidal sites in anesthetized rabbits, we have now demonstrated that increases in ear pinna cutaneous sympathetic nerve discharge can be elicited only from sites within 1 mm of the ventral surface of the medulla. By comparing the latency to sympathetic discharge following stimulation at the ventral raphe site with the corresponding latency following stimulation of the spinal cord [ third thoracic (T3) dorsolateral funiculus] we determined that the axonal conduction velocity of raphe-spinal neurons exciting ear pinna sympathetic vasomotor nerves is 0.8 +/- 0.1 m/s (n = 6, range 0.6-1.1 m/s).  

linearis caudalis region of the ventral raphe.  

hypoglossus, ventral raphe and large parts of the medullary reticular formation.  

Different effects of PCPA treatment on serotoninergic raphe nuclei were observed: dorsal raphe nucleus (DRN) seemed to be more sensitive to the PCPA's action than ventral raphe nucleus (VRN).  

The medullary raphe nuclei, wherein serotonin (5-HT) coexists with substance P (SP) and thyrotropin-releasing hormone (TRH), innervate lower motor neurons in the spinal cord ventral horn by means of the ventral raphe-spinal pathway. Destruction of the ventral raphe-spinal pathway is associated with deficient recovery of denervated muscle, indicating that it may exert a trophic effect upon lower motor neurons. To determine whether SP could be a trophic factor for lower motor neurons within the ventral raphe-spinal pathway, the effect of muscle denervation with botulinum toxin type A on SP-encoding beta-preprotachykinin mRNA in the rat medullary raphe was examined by in situ hybridization histochemistry.  

Fos-like immunoreactivity that was found in the vocalizing but not in the non-vocalizing animals was located in the dorsomedial and ventrolateral prefrontal cortex, anterior cingulate cortex, ventrolateral premotor cortex, sensorimotor face cortex, insula, inferior parietal cortex, superior temporal cortex, claustrum, entorhinal and parahippocampal cortex, basal amygdaloid nucleus, anterior and dorsomedial hypothalamus, nucleus reuniens, lateral habenula, Edinger-Westphal nucleus, ventral and dorsolateral midbrain tegmentum, nucleus cuneiformis, sagulum, pedunculopontine and laterodorsal tegmental nuclei, ventral raphe, periambigual reticular formation and solitary tract nucleus.  

5HT-positive and PR-positive cells were counted in the same area of the dorsal and ventral raphe of adjacent sections at 4 representative levels and the PR/5HT ratio was calculated. E-treatment significantly increased the number of PR-positive cells and the PR/5HT ratio in the dorsal and ventral raphe.  

In the midbrain, significant binding was restricted to the ventral raphe complex and the inferior colliculus.  

The present study was conducted (a) to determine if cross-supersensitivity at spinal noradrenergic receptors could be demonstrated in antinociceptive tests following depletion of spinal cord 5-hydroxytryptamine (5HT) by the intrathecal (i.t.) and intracerebroventricular (i.c.v.) administration of 5,7-dihydroxytryptamine (5,7DHT), and (b) to compare the pattern of supersensitivity at spinal 5HT receptors following these manipulations and 5,7DHT microinjected into the ventral raphe (VR) region and the nucleus raphe magnus (NRM).  

Furthermore, a dense accumulation of VP fibers was observed in areas such as the DBB, medial septum, BST, amygdala, hippocampus, ventral tegmental area, periaquaductal gray, dorsal and ventral raphe, area of Forel, LC region, parabrachial nuclei, and NTS.  

Stimulation of dorsal sites (the dorsal raphe obscurus) evoked a pressor/tachycardia response and stimulation of ventral sites (the ventral raphe obscurus, raphe magnus and raphe pallidus) produced a pressor/bradycardia response.  

Lesions to descending pathways by microinjection of 5,7-DHT into the ventral raphe or nucleus raphe magnus did not affect the action of baclofen significantly.  

The lateral fusion raphes, which bifurcate in hypospadias from the ventral raphe toward the dogears of the skin hood, are then opened and sutured longitudinally, as fusion should have occurred.  

5,7-Dihydroxytryptamine (5,7-DHT) injections in the ventromedial tegmentum (VMT) at the level of nucleus interpeduncularis or in the ventral raphe area (VR) of the medulla oblongata were used to study the separate roles of forebrain and spinal 5-HT in the antinociceptive effect of morphine in rats.  

The posterior and ventral raphe nuclei, which are well developed at the time of hatching, have not been visualized in the adult stickleback.  

In cats the dorsal and the ventral raphe were also labelled.  

Thus, IA cells occurred in the myelinated bundles, and sometimes in reticular formation, bordering the raphe nuclei; in the ventral brainstem forming a lateral extension from the ventral raphe (RP, RM, RPo, RCS, and LI) to the position of the rubrospinal bundle; in the periventricular gray and subjacent tegmentum of dorsal pons and caudal mesencephalon; in the locus coeruleus (LC) complex; around the motor trigeminal nucleus; caudal to the red nucleus; and in the interpeduncular and interfascicular nuclei.  

The electrical stimulation of either structure did not significantly change the content of 5-HTP and DOPA, but stimulation of nucleus accumbens depressed the level of serotonin in the neurocytes of dorsal and ventral raphe nuclei..  

In rats, lesions were placed in the dorsal/median raphe (DMR), in the ventral raphe (VR: raphe magnus), in both the dorsal/median and ventral raphe (DMVR) or in the reticular formation (RF). These findings suggest that the ascending and descending fiber systems emanating from the dorsal/median and ventral raphe, respectively, facilitate the expression of morphine-induced analgesia but that neither system alone can be regarded as essential for the manifestation of the antinociceptive effects of systematically administered morphine..  

Lesion of the midbrain ventral raphe nucleus greatly improves the avoidance-learning efficiency of normal and isolated-aggressive Albino Swiss mice.  

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