Projections of the sensory trigeminal nucleus in a percomorph teleost
 tilapia (Oreochromis niloticus)

Hao-Gang Xue
Naoyuki Yamamoto
Chun-Ying Yang
Gulnisa Kerem
Masami Yoshimoto
Nobuhiko Sawai
Hironobu Ito
Hitoshi Ozawa

The sensory trigeminal nucleus of teleosts is the rostralmost nucleus among the trigeminal sensory nuclear group in the rhombencephalon. The sensory trigeminal nucleus is known to receive the somatosensory afferents of the ophthalmic
 maxillar
 and mandibular nerves. However
 the central connections of the sensory trigeminal nucleus remain unclear. Efferents of the sensory trigeminal nucleus were examined by means of tract-tracing methods
 in a percomorph teleost
 tilapia. After tracer injections to the sensory trigeminal nucleus
 labeled terminals were seen bilaterally in the ventromedial thalamic nucleus
 periventricular pretectal nucleus
 medial part of preglomerular nucleus
 stratum album centrale of the optic tectum
 ventrolateral nucleus of the semicircular torus
 lateral valvular nucleus
 prethalamic nucleus
 tegmentoterminal nucleus
 and superior and inferior reticular formation
 with preference for the contralateral side. Labeled terminals were also found bilaterally in the oculomotor nucleus
 trochlear nucleus
 trigeminal motor nucleus
 facial motor nucleus
 facial lobe
 descending trigeminal nucleus
 medial funicular nucleus
 and contralateral sensory trigeminal nucleus and inferior olive. Labeled terminals in the oculomotor nucleus and trochlear nucleus showed similar densities on both sides of the brain. However
 labelings in the trigeminal motor nucleus
 facial motor nucleus
 facial lobe
 descending trigeminal nucleus
 and medial funicular nucleus showed a clear ipsilateral dominance. Reciprocal tracer injection experiments to the ventromedial thalamic nucleus
 optic tectum
 and semicircular torus resulted in labeled cell bodies in the sensory trigeminal nucleus
 with a few also in the descending trigeminal nucleus. c 2006 Wiley-Liss
 Inc.

Journal of Comparative Neurology

495

3

10.1002/cne.20865

https://doi.org/10.1002/cne.20865
https://www.ncbi.nlm.nih.gov/pubmed/16440296