In animals treated with amitriptyline, IA acquisition did not modify CO activity in any of these regions, but increased it in the anteromedial nucleus of the thalamus, the diagonal band of Broca, and the dentate gyrus. 
The anteromedial nucleus (AM) receives mainly ipsilateral projections from the prelimbic and medial orbital cortices and bilateral projections from the anterior cingulate and secondary motor cortices.
The projections from the anteromedial nucleus of the thalamus (AM) were investigated using anterograde and retrograde tracing techniques.
Thalamic labeling after cFr2 injections was present in anteromedial nucleus (AM), ventrolateral nucleus (VL), lateral segment, mediodorsal nucleus (MDl), centrolateral nucleus (CL), ventromedial nucleus (VM), posterior nucleus (Po) and lateral posterior nucleus (LP).
Caudal area 29d projects mainly ipsilaterally to the rostrodorsal part of the anteromedial nucleus, and the rostral and dorsal parts of the anteroventral nucleus, whereas rostral area 29d projects bilaterally to the caudodorsal part of the anteromedial nucleus and the caudolateral part of the anteroventral nucleus.
Following injections of the fluorescent dyes, serial coronal sections of the brain revealed single retrogradely labelled, and large numbers of double retrogradely labelled neuronal cell bodies in the ipsilateral anteroventral and anterodorsal nuclei and smaller numbers in the anteromedial nucleus of the ATN complex.
The same region was reciprocally connected with the anteromedial nucleus of the thalamus, which received input from the rostral subiculum.
The relevant medial hypothalamic nuclei receive pheromonal information from the amygdala and project to specific parts of the thalamic nucleus reuniens and anteromedial nucleus, which then project to a specific lateral part of the retrosplenial area (or medial visual cortex).
The anteromedial nucleus (AM) projects to the temporal subiculum, medial entorhinal area, perirhinal area, and caudomedial part of the lateral entorhinal area. The interanteromedial nucleus (IAM) projects to the perirhinal area and the caudolateral part of the lateral entorhinal area.
The rostral part of the anteromedial nucleus projects to layers I, V and VI of the anterior cingulate areas 1 and 2, layers I and III of the ventral orbital area, layers I, V and VI of area 29D of the retrosplenial area, and layers I and V of the caudal part of the retrosplenial granular and agranular areas. In contrast, the caudal part of the anteromedial nucleus projects to layer V of the frontal area 2, and layers I and V of the rostral part of the retrosplenial granular and agranular areas. The interanteromedial nucleus projects to layers I, III and V of the frontal area 2, layer V of the agranular insular area, and layers I, V and VI of area 29D.
The dorsal region of the pars mediana of the MM projects to the interanteromedial nucleus (IAM), whereas the ventral region projects to the rostral part of the anteromedial nucleus (AM).
Those from the anteromedial nucleus terminate predominantely in layers I and IV-VI, whereas the axons arising from the laterodorsal nucleus have a dense terminal plexus in layers I and III-IV.
The anteromedial nucleus projects generally to both areas 24 and 29, but principally to anterior area 24. Collaterals (9-13%) from the anteromedial nucleus project diffusely to areas 24 and 29, while collaterals from other nuclei project primarily to areas adjacent to each other.
The bulk of the neurons of the anteromedial nucleus are generated over a 2-day period between days E16-E17 and show the same settling pattern as the anteroventral nucleus. On day E17 the putative migratory stream of the anteromedial nucleus appears to leave the same neuroepithelial region that on the previous days was the source of the anteroventral nucleus.
Thalamic projections to CGa, in descending order of strength, originate in the anteromedial nucleus, lateroposterior nucleus, ventroanterior nucleus, rostral intralaminar complex, reuniens nucleus, mediodorsal nucleus, and laterodorsal nucleus.
Nicotine significantly increased LCGU in a dose-dependent manner in the following 9 of 45 examined structures: substantia nigra (compact part), superior colliculus (superficial grey layer), interpeduncular nucleus and cingulate cortex (P less than 0.01); lateral geniculate body, optic chiasm, anteroventral and anteromedial nucleus of thalamus and mamillary body (P less than 0.05).
Projections to mesial thalamic nuclei, specifically to the anteromedial nucleus, the midline nuclei, and the magnocellular part of the mediodorsal nucleus are bilateral, the contralateral projection being nearly as dense as the ipsilateral projection.
Nicotine significantly increased LCGU in a dose-dependent manner in the following 9 of 45 examined structures: substantia nigra (compact part), superior colliculus (superficial grey layer), interpeduncular nucleus and cingulate cortex (P less than 0.01); lateral geniculate body, optic chiasm, anteroventral and anteromedial nucleus of thalamus and mamillary body (P less than 0.05).
The caudal part of the cingulate gyrus receives fibers from the medial part of the anteromedial nucleus (AM) and the rostromedial part of the anteroventral nucleus (AV).
Retrograde cellular labeling also occurs within the anteromedial nucleus (AM) following these injections.
The activity of anteromedial nucleus neurons was lower and much more uniform; it consisted of alternating randomized spikes and "inactivation bursts".
All limbic cortical areas send projections bilaterally to all regions of the anteromedial nucleus as well as to the parvicellular parts of the anteroventral thalamic nucleus, while the anterodorsal nucleus receives ipsilateral projections originating exclusively from the preagranular, anterior limbic, and cingular regions.
At this same level, a very light projection was seen in the contralateral anteromedial nucleus.
As in the rat, only the sulcal prefrontal cortex seems to be reached by mediodorsal cells alone, whereas the rest of the prefrontal cortical fields have overlapping projections from the anteromedial nucleus.
Additionally, HRP-labeled neurons were found in the ventrolateral portions of the anteromedial nucleus (AM), lateral portions of the MD, ventral tegmental area of Tsai (vT) and the midline raphe nuclei, such as the rostral lineal (rL), central lineal (cL) and dorsal raphe (dR) nuclei..
The anterior limbic region receives fibers largely from the anteromedial nucleus and partly from the anterodorsal and anteroventral nuclei. There appears to be a dorsoventral organization of cortical projections of the anteromedial nucleus to the anterior limbic region.
The anteromedial nucleus sends fine fibers to the anterior limbic region and to the cingular, retrosplenial, postsubicular and presubicular areas. The cortical projections of the anteromedial nucleus appear to be topographically organized in the dorsoventral direction. Fibers from the anteromedial nucleus are distributed largely in cortical layers V and VI of the anterior and posterior limbic regions..
The anteromedial nucleus does not appear to project to layer III of the projection field of the mediodorsal nucleus, although it may project to layers I and VI, especially in the anterior cingulate and medial precentral areas.
A comparison of the patterns of retrograde cell-labeling charted in 26 such cases confirmed earlier findings in fiber-degeneration studies according to which the respective thalamocortical projections of the mediodorsal (MD) and anteromedial nucleus (AM) overlap each other over a wide region of the anterior medial cortex.
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