链霉素耳中毒豚鼠耳蜗iNOS与AChE的表达及其相关性的实验研究

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酶（inducible nitric oxide synthase,iNOS）与乙酰胆碱酯酶（acetylcholine esterase,AChE）的表达及二者之间的相关性。方法16只豚鼠随机分为正常对照组和SM组,每组8只,分别每日腹腔注射生理盐水2.5ml/kg和SM150mg/kg,连续10日。应用免疫组织化学染色及图像分析技术检测耳蜗iNOS和AChE的表达并进行灰度值分析,结合听性脑干反应（auditory brainstem response,ABR）测试监测耳毒性损伤的发生。结果用药10d后,SM组ABR阈值明显高于正常对照组,两组差异有统计学意义（P〈0.01）。免疫组化结果表明,SM组iNOS及AChE在柯蒂器、血管纹、螺旋神经节、神经纤维的表达显著高于正常对照组,且二者表达呈正相关。结论SM耳中毒时ABR阈值升高,iNOS及AChE表达增强,而且具有一定的相关性。

A Correlativity Study About of the Expression of iNOS and AChE on Guinea Pigs Cochlea Damaged by Streptomycin

Objective To study the expression of iNOS and AChE during streptomycin ototoxicity and the correlation.Methods 16 guinea pigs were divided into 2 groups randomly:control group and SM group.SABC immunohistochemical staining and image quantitative analysis technique were used to observe the expression of iNOS and AChE and grey value analysis.ABR measurements were used to monitor the effects of ototoxity.Results After 10 days with drugs,the ABR threshold value of SM group increased more significantly than that of the control group(P<0.01).The result of immunohistochemical staining indecated the expression of iNOS and AChE in CO,IHC and OHC,SG,SV of SM group were higher than that of control group,demonstrating positive correlation.Conclusion The ABR threshold value increased and the expression of iNOS and AChE strengthen on SM ototoxity,and had some correlation.