A Method for Establishing an Animal Model of Like-Auditary Neuropathy

Objective:To establish an animal model of like-auditory neuropathy in neonatal rat.MethodsThe animals were injected with phenylhydrazine hydrochloride or saline at 7-day of age. ABR and DPOAE were performed to assess the auditory function. The cochlea basilar membrane stretched preparation and cochlear frozen sections were prepared for immunohistochemical staining to examine the morphological change of hair cells and spiral ganglion cells (SGNs).ResultsAt 7-day age the ABR waveI, III, V, latencies andI- III,I-V IWIs in the experimental group were significantly prolonged compared with those in the control group. The ABR thresholds were also elevated in the experimental group. We found there is no significant difference in DPOAE in phenylhydrazine hydrochloride exposure group compare to control group. The cochlear hair cells showed no signs of loss in both group, but the total number of neurofilaments positive cells in SGNs were significantly reduced in the phenylhydrazine treated animals.ConclusionOur study suggests that phenylhydrazine hydrochloride can change the auditory function and induce peripheral nerve pathology by targeted mainly the SGNs in neonatal rat.