ABSTRACT
Objective: A traditional Chinese medicine(TCM) transformed from Jian Er Ⅱ,Cong Er capsule was studied in protection against age-induced degeneration in cochlear spiral ganglion neurons and auditory nerve fibers in C57 BL /6J mice.A possible protective mechanism was also discussed.Methods : 40 neonatal C57 BL /6J mice were randomly divided into 2 groups with an average of 20 animals in each group.The animals in control group were fed with regular mouse feedstuff and regular water after ablactation,while animals in experimental group were fed the same mouse food after ablactation,but drink the medical solution of Cong Er capsule instead of regular water from two months of age.Animals were terminated at 7 months of age.The cochlea were removed and processed for a series of modiolus sections.The density of spiral ganglion neurons in Rosenthal's canal in different turns was counted,and the auditory nerve fibers in habenula perforata at basal turn and apical turn were also quantified respectively.Statistical comparative analysis was performed between the two groups.Results: Density of spiral ganglion neurons in cochlear basal turn in control group was significantly reduced.In survival ganglion neurons,an obvious degeneration was observed in control group.The number of auditory nerve fibers in cochlear basal turn also decreased.In contrast,Cong Er capsule treated animals had an increase in survival ganglions and auditory nerve fibers,especially,a significant difference was seen in density of spiral ganglion neurons in the basal turn between the two groups(P