Parataenial Nucleus Of Thalamus


The medial orbital area receives its principal thalamic afferents from the parataenial nucleus, the dorsocentral portion of the mediodorsal nucleus, and the ventromedial portion of the submedial nucleus.  

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.  

The projections of the parataenial nucleus are directed towards central and ventral parts of the nucleus accumbens and intermediate mediolateral parts of the olfactory tubercle.  

Distribution: A large number of enkephalin-like immunoreactive (ENKI) terminals were observed in the antero-ventral nucleus (AV), the region between the parataenial nucleus, the antero-medial thalamic nucleus and ventral part of the ventral nucleus.  

High affinity uptake of D-[ 3H]aspartate, [ 3H]choline and [ 3H]GABA was examined in synaptosomal-containing preparations of rat nucleus accumbens septi 7 to 10 days after unilateral or bilateral N-methyl-D-aspartate lesions confined to the parataenial nucleus of the thalamus or the basolateral nucleus of the amygdala.  

Following infusion of D[ 3H]aspartate, ipsilateral midline thalamic nuclei contained the highest density of labelled perikarya; infusions centred on nucleus accumbens resulted in heavy retrograde labelling of the parataenial nucleus, but labelling was sparse from a lateral site and not observed after injection into anterior caudate-putamen.  

The fourth consists of fibers just caudal to the third group that end in the preoptic continuation of the bed nucleus of the stria terminalis, as well as in the parataenial nucleus and rostral part of the paraventricular nucleus of the thalamus.  

Cells with CCK-IR were also found in the caudal group of the intralaminar nuclei, in the paraventricular nucleus and the parataenial nucleus.  

In this study the intrastriatal distribution of afferents arising from the parataenial nucleus of the thalamus was investigated. Tritiated leucine and proline injected into the parataenial nucleus was found to densely label the entire anterior-posterior extent of the medial nucleus accumbens. Other efferent connections of the parataenial nucleus observed in this study include the thalamic reticular nucleus, the basolateral and central nuclei of the amygdala, the septum, the medial frontal cortex, the entorhinal cortex and subiculum. The present findings suggest that the parataenial nucleus is an important thalamic link between limbic and striatal processing..  

The medial septal nucleus also sends fibers to the midbrain (the ventral tegmental area and raphe nuclei) and to the parataenial nucleus of the thalamus, while the nucleus of the diagonal band has an additional projection to the anterior limbic area.  


-
[ View All ]