Ipsilateral and contralateral projections from upper cervical segments to the vestibular nuclei in the rat

Citation
Gx. Xiong et M. Matsushita, Ipsilateral and contralateral projections from upper cervical segments to the vestibular nuclei in the rat, EXP BRAIN R, 141(2), 2001, pp. 204-217
Citations number
56
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Neurosciences & Behavoir
Journal title
EXPERIMENTAL BRAIN RESEARCH
ISSN journal
0014-4819 → ACNP
Volume
141
Issue
2
Year of publication
2001
Pages
204 - 217
Database
ISI
SICI code
0014-4819(200111)141:2<204:IACPFU>2.0.ZU;2-R
Abstract
The present study examined uncrossed and crossed projections from upper cer vical segments to the vestibular nuclei, and the relationship between the a fferent,,, and vestibulospinal neurons in the rat. Afferent axons were labe led following unilateral injections of biotinylated dextran into the C2 and C3 segments, while vestibulospinal neurons were labeled following unilater al injections of cholera toxin subunit B into the same segments. The termin als of uncrossed afferents were distributed in the entire area of the rostr ocaudal extent of the lateral vestibular nucleus (LV). In the magnocellular part (MVmc) of the medial vestibular nucleus (MV), they were seen near the parvocellular part (MVpc) of the MV at caudal levels. In the MVpc, termina ls were seen laterally and ventromedially, close to the border of the MVmc. At caudal levels of the caudal part (MVc) of the MV, they were distributed within the groups of labeled neurons in the middle and lateral C areas. In the descending vestibular nucleus (DV), terminals were abundant dorsally a nd laterally in the rostral two-thirds. The distribution of contralateral c ervical afferents was similar to that of ipsilateral afferents. The termina ls of ipsilateral and contralateral cervical afferents were seen in contact with vestibulospinal neurons in the DV. The present study demonstrates bil ateral input from upper cervical segments to the LV, DV, and all subdivisio ns of the MV. The input to the LV would contribute to the tonic neck reflex or cervicovestibulospinal reflex.