iNOS在链霉素耳中毒豚鼠耳蜗血管纹的表达

目的探讨链霉素（streptomycin,SM）耳中毒过程中豚鼠耳蜗诱生型一氧化氮合霉（inducible nitric oxide synthase,iNOS）的表达.方法 20只豚鼠随机分为正常对照组、SM组,每组10只,SM组每日腹腔注射硫酸链霉素150 mg/kg,正常对照组每日腹腔注射等量生理盐水,用药10天后处死.以听性脑干反应（ABR）为监测指标,结合电镜、免疫组化及图像分析技术,检测链霉素耳中毒过程中耳蜗血管纹iNOS的表达及形态学改变.结果用药10天后,SM组ABR阈值明显高于正常对照组,有统计学差异（P〈0.01）,电镜下可见SM组血管纹损伤严重;免疫组化结果表明,SM组血管纹iNOS的表达明显高于正常对照组.结论 SM耳中毒时ABR阈值升高,血管纹iNOS表达增强.

Expression of Inducible Nitric Oxide Synthase in the Cochlear Stria Vascularis of Guinea Pig Damaged By Streptomycin

Objective To investigate the expression of inducible nitric oxide synthase(iNOS) in the cochlear stria vascularis(SV) of guinea pigs after streptomycin(SM).Methods Auditory brainstem response(ABR) was used as measurement index,and combining with transmission electron microscope(TEM),immunohistochemical staining and image quantitative analysis technique, to detect iNOS expression in the cochlea stria vascularis of guinea pigs and the change of morphology after SM.Results 10 days after adminitration, ABR threshold of SM group increased more significantly than that of the control group(P<0.01).Stria vascularis damaged greatly under TEM observation.The result of immunohistochemical staining implied that iNOS expression in SV of SM group was stronger than that of the control group.Conclusion ABR threshold increases and the expression of iNOS of stria vascularis strengthens during SM ototoxity.