血清一氧化氮变化对豚鼠庆大霉素耳毒性作用影响的实验研究

目的:探讨豚鼠血清一氧化氮变化在药物性耳聋过程中的作用机制. 方法:24只健康豚鼠随机均分为正常组、庆大霉素组、庆大霉素加L.精氨酸(全程)组和庆大霉素加L一精氨酸(半程)组.观察各种豚鼠血清中一氧化氮、听觉脑干反应、内耳外毛细胞的形态学变化. 结果:庆大霉素组血清中一氧化氮与正常组差异无统计学意义(P＞0.05);L-精氨酸全程组和半程组治疗后血清中一氧化氮高于正常组和庆大霉素组(P＜0.05～P＜0.01).L一精氨酸组ABR反应阈较庆大霉素组降低(P＜0.05).L-精氨酸组内耳外毛细胞仅有散在损失. 结论:一氧化氮一定量升高对内耳毛细胞有细胞毒性作用,进一步升高则对外毛细胞有保护作用.L-精氨酸治疗能降低ABR阈值,减少外毛细胞损害,对耳蜗有保护作用.

Influence of the change of nitric oxide in serum of guinea pigs on the ototoxicity gentamycin:An experimental study

Objective:To explore the influence of nitric oxide in serum on aminoglycoside antibiotic induced deafness in guinea pigs and its mechanism.Methods:Twenty four health guinea pigs were randomly divided into four groups:6 animals acted as normal controls,6 were given gentamyin,6 gentamyin with L-arginine from 1 to 19 days and 6 gentamycin with L-arginine from 10 to 19 days.Then the nitric oxide in serum was measured.The threshold of auditory brainstem response(ABR) and the pathological morphology of outer hair cells in the inner ear were evaluated.Results:The nitric oxide in serum of the gentamycin group was not significantly higher than that of the normal control group(P>0.05),the ABR threshold(95.63 dB) was significantly higher than that of the normal control group(P<0.05),and the outer hair cells were massively lost.The nitric oxide in serum in the L-arginine groups was much higher than that in the normal control group and that in the gentamycin groups(P<0.001-P<0.005),but the ABR threshold was lower than that in the gentamycin group and the outer hair cells were sporadically lost.Conclusions:Some degree of nitric oxide in serum may cause toxicity to outer hair cells in guinea pigs,but higher level of nitric oxide in serum may be effective in prevention of outer hair cells in guinea pigs.The L-arginine may decrease ABR threshold and alleviate outer hair cells injury,which has preventive effect to the cochlea of guinea pigs.