丹参注射液对庆大霉素耳中毒豚鼠耳蜗氧自由基生成的影响

EFFECTS OF INJECTIO SALVIA MILTIORRHIZA ON GENTAMICIN INDUCED FREE RADICAL FORMATION IN GUINEA PIG COCHLEA

目的研究丹参注射液(SM)对庆大霉素(GM)耳中毒豚鼠耳蜗氧自由基生成的影响,探讨SM对GM耳毒性损伤的保护作用及其机制。方法检测豚鼠耳蜗组织中超氧化物歧化酶(SOD)活力和丙二醛(MDA)含量,结合听性脑干反应(ABR)测试及透射电镜技术。结果经GM处理的耳蜗组织中SOD活力明显下降,MDA含量则明显增加(P<0.01),且与ABR阈值升高高度相关(|r|>0.8,P<0.05)。同时接受SM的动物,其耳蜗组织中SOD活力明显升高(P<0.01),MDA含量则明显减少(P<0.05),且听功能显著改善。电镜观察显示耳蜗形态学改变与听力变化相一致。结论氧自由基及其引发的脂质过氧化参与了GM耳中毒过程,SM可通过提高耳蜗组织中SOD活力,防止脂质过氧化,减轻GM的耳蜗毒性,改善听功能。

Aim:To investigate the effects of injectio Salvia Miltiorrhiza (SM) on gentamicin (GM) induced free radical formation in guinea pig cochlea, and to explore possible mechanisms on GM induced ototoxicity. Methods: Biochemical assays of superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in guinea pig cochlea, combined with auditory brainstem response (ABR) measurement and transmission electron microscopic observation were used in this investigation. Results: SOD activity was significantly declined while MDA content was distinctly increased in cochlear tissues after GM injection ( P <0.01). Moreover, they were well correlated with auditory function damage (｜r｜>0.7). Co treatment with SM evidently enhanced SOD activity and decreased MDA content ( P <0.01, P <0.05). Furthermore, auditory function was markedly ameliorated. Morphological changes of cochlea were consistent with those of hearing function. Conclusion: Lipid peroxidation elicited by free radical was involved in GM induced cochleotoxicity. SM might enhance SOD activity and prevent lipid peroxidation. As the result it might alleviate GM ototoxicity, and improve auditory function.