At anterior hypothalamic levels, a moderate number of branched fibers was observed in the paraventricular nucleus, in addition to a small number of poorly branched axons in the anterior periventricular nucleus, anterior hypothalamic nucleus, and lateral part of the retrochiasmatic area (Fig. 2B). Most of the anterograde labeling observed in the paraventricular nucleus tended to be confined to the anterior and dorsal parvicellular parts (Fig. 2B).

At anterior hypothalamic levels, a moderate number of branched fibers was observed in the paraventricular nucleus, in addition to a small number of poorly branched axons in the anterior periventricular nucleus, anterior hypothalamic nucleus, and lateral part of the retrochiasmatic area (Fig. 2B). Most of the anterograde labeling observed in the paraventricular nucleus tended to be confined to the anterior and dorsal parvicellular parts (Fig. 2B).

At anterior hypothalamic levels, a moderate number of branched fibers was observed in the paraventricular nucleus, in addition to a small number of poorly branched axons in the anterior periventricular nucleus, anterior hypothalamic nucleus, and lateral part of the retrochiasmatic area (Fig. 2B). Most of the anterograde labeling observed in the paraventricular nucleus tended to be confined to the anterior and dorsal parvicellular parts (Fig. 2B).

At anterior hypothalamic levels, a moderate number of branched fibers was observed in the paraventricular nucleus, in addition to a small number of poorly branched axons in the anterior periventricular nucleus, anterior hypothalamic nucleus, and lateral part of the retrochiasmatic area (Fig. 2B). Most of the anterograde labeling observed in the paraventricular nucleus tended to be confined to the anterior and dorsal parvicellular parts (Fig. 2B).

At anterior hypothalamic levels, a moderate number of branched fibers was observed in the paraventricular nucleus, in addition to a small number of poorly branched axons in the anterior periventricular nucleus, anterior hypothalamic nucleus, and lateral part of the retrochiasmatic area (Fig. 2B). Most of the anterograde labeling observed in the paraventricular nucleus tended to be confined to the anterior and dorsal parvicellular parts (Fig. 2B).

At anterior hypothalamic levels, a moderate number of branched fibers was observed in the paraventricular nucleus, in addition to a small number of poorly branched axons in the anterior periventricular nucleus, anterior hypothalamic nucleus, and lateral part of the retrochiasmatic area (Fig. 2B). Most of the anterograde labeling observed in the paraventricular nucleus tended to be confined to the anterior and dorsal parvicellular parts (Fig. 2B).

At anterior hypothalamic levels, a moderate number of branched fibers was observed in the paraventricular nucleus, in addition to a small number of poorly branched axons in the anterior periventricular nucleus, anterior hypothalamic nucleus, and lateral part of the retrochiasmatic area (Fig. 2B). Most of the anterograde labeling observed in the paraventricular nucleus tended to be confined to the anterior and dorsal parvicellular parts (Fig. 2B).

a group of fibers also extend laterally from the injection site, and appear to provide significant inputs to a circumscribed region situated above the optic tract in the lateral hypothalamic area (Fig. 2D) .

Proceeding rostrally, a small contingent of ascending fibers from the RCHb projects to the preoptic region, providing sparse inputs to the preoptic periventricular nucleus, suprachiasmatic preoptic nucleus, anteroventral periventricular nucleus and medial part of the medial preoptic nucleus (Fig. 2A).

Proceeding rostrally, a small contingent of ascending fibers from the RCHb projects to the preoptic region, providing sparse inputs to the preoptic periventricular nucleus, suprachiasmatic preoptic nucleus, anteroventral periventricular nucleus and medial part of the medial preoptic nucleus (Fig. 2A).

Proceeding rostrally, a small contingent of ascending fibers from the RCHb projects to the preoptic region, providing sparse inputs to the preoptic periventricular nucleus, suprachiasmatic preoptic nucleus, anteroventral periventricular nucleus and medial part of the medial preoptic nucleus (Fig. 2A).

A group of axons leaves the hypothalamus by taking either a dorsolateral route toward the bed nuclei of the stria terminalis (BST) or a dorsal route, rostral to the anterior commissure, to project to the lateral septal nucleus, providing a rather sparse projection, respectively, to the anteroventral area of the BST (Fig. 2A) and the intermediate part of the lateral septal nucleus.

A group of axons leaves the hypothalamus by taking either a dorsolateral route toward the bed nuclei of the stria terminalis (BST) or a dorsal route, rostral to the anterior commissure, to project to the lateral septal nucleus, providing a rather sparse projection, respectively, to the anteroventral area of the BST (Fig. 2A) and the intermediate part of the lateral septal nucleus.

From the septal area, a few axons were also labeled in the fimbria extending to ventral regions of field CA1 in Ammon’s horn and ventral subiculum.

From the septal area, a few axons were also labeled in the fimbria extending to ventral regions of field CA1 in Ammon’s horn and ventral subiculum.

A small number of fibers from the RCHb that ascend through the hypothalamus may also enter the thalamus, where they appear to provide a rather sparse innervation to the nucleus reuniens, paraventricular nucleus and parataenial nucleus.

A small number of fibers from the RCHb that ascend through the hypothalamus may also enter the thalamus, where they appear to provide a rather sparse innervation to the nucleus reuniens, paraventricular nucleus and parataenial nucleus.

A small number of fibers from the RCHb that ascend through the hypothalamus may also enter the thalamus, where they appear to provide a rather sparse innervation to the nucleus reuniens, paraventricular nucleus and parataenial nucleus.

Axons descending through the medial and periventricular zones of the hypothalamus provide substantial inputs to the central and ventrolateral parts of the ventromedial nucleus (Fig. 2C).

Axons descending through the medial and periventricular zones of the hypothalamus provide substantial inputs to the central and ventrolateral parts of the ventromedial nucleus (Fig. 2C).

...small projections to the arcuate nucleus and to the anterior part of the dorsomedial nucleus were also observed (Fig. 2C).

...small projections to the arcuate nucleus and to the anterior part of the dorsomedial nucleus were also observed (Fig. 2C).

Proceeding caudally, axons following this pathway give rise to a small terminal field in the posterior hypothalamic nucleus and enter the midbrain periventricular system.

A few labeled fibers from the RCHb passing through the rostral pole of the periaqueductal gray split off to project to the pretectal region and several thalamic nuclei, including the lateral posterior nucleus, lateral geniculate body and medial geniculate body.

A few labeled fibers from the RCHb passing through the rostral pole of the periaqueductal gray split off to project to the pretectal region and several thalamic nuclei, including the lateral posterior nucleus, lateral geniculate body and medial geniculate body.

A few labeled fibers from the RCHb passing through the rostral pole of the periaqueductal gray split off to project to the pretectal region and several thalamic nuclei, including the lateral posterior nucleus, lateral geniculate body and medial geniculate body.

A few labeled fibers from the RCHb passing through the rostral pole of the periaqueductal gray split off to project to the pretectal region and several thalamic nuclei, including the lateral posterior nucleus, lateral geniculate body and medial geniculate body.

A few labeled fibers from the RCHb passing through the rostral pole of the periaqueductal gray split off to project to the pretectal region and several thalamic nuclei, including the lateral posterior nucleus, lateral geniculate body and medial geniculate body.

A few labeled fibers from the RCHb passing through the rostral pole of the periaqueductal gray split off to project to the pretectal region and several thalamic nuclei, including the lateral posterior nucleus, lateral geniculate body and medial geniculate body.

Axons from the RCHb descending through the midbrain periventricular system provide a rather dense terminal field in the lateral part of the periaqueductal gray extending from the level of the oculomotor nucleus to its caudal end (Fig. 2E). Collator note: Atlas Level 46, Swanson rat brain atlas.

Axons from the RCHb descending through the midbrain periventricular system provide a rather dense terminal field in the lateral part of the periaqueductal gray extending from the level of the oculomotor nucleus to its caudal end (Fig. 2E). Collator note: Atlas Level 46, Swanson rat brain atlas. PAgdl also appears labeled, ventrally at least.

Proceeding caudally, labeled axons extend from the periaqueductal gray into the pontine central gray, where they seem to provide a substantial projection to Barrington’s nucleus (Fig. 2F).

Moreover, a few of these fibers arch laterally to project to the lateral part of the parabrachial nucleus.

Throughout the entire length of the reticular core of the brainstem, only a few labeled axons were observed that could be traced to the medial part of the nucleus of the solitary tract and dorsal motor nucleus of the vagus.

Throughout the entire length of the reticular core of the brainstem, only a few labeled axons were observed that could be traced to the medial part of the nucleus of the solitary tract and dorsal motor nucleus of the vagus.

Some of these fibers [collator note: from NTSm and DMX] extend caudally around the central canal of the spinal cord, where at thoracic levels a few of them could be traced to the intermediolateral cell column.

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent

Collator note: all Atlas Levels have been analyzed and this projection was demonstrated to be absent