[Quantitation of nerve fibers in habenula perforata in chinchilla].
OBJECTIVE
To examine the number of nerve fibers in the habenula perforata of the cochlea in normal and carboplatin-treated chinchillas.


METHODS
Three months following administration of carboplatin (100 mg/kg x 2), six carboplatin-treated animals, together with 6 controls, were sacrificed, prepared for semi-thin sectioning of the cochlea. The sections were stained with toluidine blue and basic fuchsin, examined under a light microscope and photographed.


RESULTS
In normal chinchillas, the numbers of the nerve fibers in each habenula opening varied across the cochlea, with 93.7 +/- 12.2(mean +/- s) fibers at the hook, 181.5 +/- 30.4 at the upper of basal turn, 129.7 +/- 27.8 at the second turn and 75.8 +/- 13.2 at the apical turn. In cochlear devoid of type I ganglion cells and inner hair cells as a result of carboplatin treatment, only one-seventh of the fiber population remained.


CONCLUSIONS
Approximately six-seventh of the nerve fibers in the habenula are type I afferent axons that innervate the inner hair cells. The remaining fibers are type II afferents and surviving efferents.
Ding
D
D
Center for Hearing and Deafness, Hearing Research Lab, SUNY University at Buffalo, USA.
Zheng
X
X
Wang
J
J
D000818:Animals; D016190:Carboplatin; D002682:Chinchilla; D003051:Cochlea / Q000294:innervation*; D015834:Cochlear Diseases / Q000139:chemically induced / Q000473:pathology*; D006199:Hair Cells, Auditory, Inner / Q000473:pathology; D009412:Nerve Fibers / Q000473:pathology*
D016190:Carboplatin