A comparative study of the tangential-oculomotor projection.
Most of the neurons of the tangential vestibular nucleus of birds project to the controlateral oculomotor complex, but it is not known whether there is a homologous projection in mammals. In this study, horseradish peroxidase (HRP) was injected into the oculomotor nucleus of chicks and rabbits, and the distributions of labelled neurons in the target region of the vestibular complex in the two species were compared. In chicks, a large number of labelled neurons formed a continuous band of neurons located in the contralateral tangential, descending and medial nuclei. In rabbits a similar band of labelled neurons was found in the contralateral descending and medial vestibular nuclei, but most of the neurons were caudal to the incoming vestibular nerve fibers, and only a few rostral neurons were located among these fibers. Our results suggest that the tangential nucleus neurons projecting to the oculomotor nucleus may be homologous to the most lateral neurons of the neuronal band of rabbits.
Labandeira-Garcia
J L
JL
Department of Morphological Sciences, University of Santiago de Compostela, Spain.
Guerra-Seijas
M J
MJ
Castroviejo-Bolivar
M A
MA
Jorge-Barreiro
F J
FJ
D000818:Animals; D002645:Chickens; D006735:Horseradish Peroxidase; D009434:Neural Pathways / Q000502:physiology; D009802:Oculomotor Nerve / Q000502:physiology*; D011817:Rabbits; D013045:Species Specificity; D014726:Vestibular Nuclei / Q000166:cytology / Q000502:physiology
D006735:Horseradish Peroxidase