Neuron-specific enolase expression and cell apoptosis in spiral ganglion in rats with air conduction hearing deprivation

ObjectiveTo observe spiral ganglion neuron-specific enolase (NSE) expression and cell apoptosis in spiral gangliion in rats with air conduction hearing deprivation. MethodsTotally 60 newborn Sprague-Dawley rats were randomly divided into auditory deprivation group (n=30) and the control group (n=30).The rats in auditory deprivation group were administered external auditory canal isolation after birth and reared in confined soundproof room.The rats in control group were reared with normal drinking water in sound environment.Auditory brainstem evoked potentials (ABR) was measured.Cohlea tissue slice and spiral ganglion staining were conducted for neuron number count and observations of NSE expression and cell structure change. ResultsThe ABR reactor threshold (38.18 ? 5.54 dB SPL) of auditory deprivation rats was significantly higher compared with that of the control group (26.67 ? 3.89 dB SPL) (P<0.01).The staining of NSE immunohistochemical neurons was pale.The neuron count (7.88 ? 0.99 per field of view) was significantly reduced in auditory deprivation rats (P<0.05).Scattered apoptotic cells were observed in spiral ganglion of auditory deprivation rats. ConclusionAir conduction hearing deprivation can decrease type I NSE expression and the number of neurons,and induce cell apoptosis in spiral ganglion of rats during development period.