庆大霉素耳毒性作用机理的实验研究

The study on mechanisms of Gentamicin ototoxicity

目的探讨庆大霉素(gentamicin GM)耳毒性作用机理。方法 Wistar大鼠随机分为GM组(皮下注射硫酸庆大霉素120 mg/kg体重,1次/日,20 d)和对照组(以生理盐水替)。并于用药后检测听性脑干反应(auditory brainstem response,ABR)的反应阈、耳蜗SOD、丙二醛、Tm值、DNA双链剩余率。结果 GM组在1和8 kHz的ABR较对照组明显增高(p<0.05,0.01),GM组的丙二醛、SOD、Tm值和双链DNA剩余率分别为4.5±1.1 mmol/mg蛋白、267±48.5 NU/mg蛋白、63.4±0.3℃、59.7±6.5%,而对照组则为2.6±1.3 mmol/mg蛋白、342±36.3 NU/mg蛋白、79.0±0.9℃、76.2±11.3%。结论自由基和DNA损伤在GM耳毒性中起重要作用。

PURPOSE To study the mechanism of Gentamicin (GM) ototoxicity.METHODS Wistar rats were randomly assigned to experimental group (GM-treated 120mg/kg/d,20 d)and control group ( normal saline).Acoustic brainstem response (ABR),MAD,SOD,Tm and double-stranded DNA were mesured.RESULTS The ABR in the GM-treated group was positively higher than that the control group at 1 and 8kHz(p&lt;0.05,0.01).The MAD,SOD,Tm and double-stranded DNA of GM-treated group were 4.5±1.1mmol/ mg proteuin,267±48.5 NU/mg protein 63.4±0.3℃,59.7±6.5% respectively,while those of the control group were 2.6±1.3 mmol/mg protein,342 ±36.3 NU/ mg protein,79.0±0.9℃,76.2+11.3%.CONCLUSION This study suggests that free radical and DNA damage were important mechanisms of GM ototoxicitv