Carboplatin results in neuron loss in the cochlear nucleus but not the inferior colliculus or auditory cortex of chinchilla
SUN Jianhe
YANG Weiyan
DING Dalian
SUN Wei
Sandra McFadden
Richard Salvi
Abstract：Objective Carboplatin selectively destroys inner hair cells (IHC)and typeⅠspiral ganglion neurons in the chinchilla cochlea;however,its effects on the central auditory system are largely unknown.The aim of this study was to determine if carboplatin treatment affects neuron survival in the cochlear nucleus (CN),inferior colliculus(IC)or auditory cortex(AC)of the chinchilla.Methods Chinchillas were treated with carboplatin(100mg/kg IP).Three weeks later,they were sacrificed and perfused intracardially with fixative.Surface preparations of Corti's organ were analyzed for hair cell loss.Serial frozen sections taken from the CN, IC and AC were stained with toluidine blue,and neurons were counted in representative sections from two normal(control)and four carboplatin-treated chinchillas. Results The results showed that carboplatin destroyed approximately 80% of the IHC,but almost none of the outer hair cells (OHC). In the central auditory system, carboplatin resulted in a significant loss of neurons in the anteroventral, posteroventral and dorsal divisions of the CN, but not in the IC or AC. Conclusionon Future studies will determine if the loss of neurons in the CN is a direct result of carboplatin neurotoxicity or a secondary effect of inner hair cell and spiral ganglion neuron loss in the auditory periphery.
Keywords：Ototoxicitycarboplatincochlear nucleusinferior colliculusauditory cortex
Publication Date：2003-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：4( 16-19 )