磷酸化JNK在庆大霉素致豚鼠前庭毛细胞凋亡中的表达

目的:观察庆大霉素致豚鼠前庭毛细胞损伤特点,并探讨磷酸化cjun氨基末端激酶(JNK)在前庭毛细胞凋亡过程中的作用机制。方法:健康豚鼠随机分为实验组和对照组各15只,分别行100mg/(kg·d)庆大霉素和生理盐水连续肌肉注射7d,第8天全身麻醉下处死豚鼠,取壶腹嵴为观察对象,左耳铺片,硝酸银染色检测毛细胞损伤;右耳冷冻连续切片,DNA末端转移酶介导的缺口末端标记法(TUNEL)检测毛细胞凋亡,免疫组织化学方法检测细胞中JNK磷酸化。结果:实验组中毛细胞受损,壶腹嵴顶端见凋亡细胞,并在细胞内观察到磷酸化JNK免疫阳性反应;对照组中未见毛细胞损伤及凋亡细胞,未见磷酸化JNK。结论:庆大霉素可以通过诱导凋亡造成内耳前庭毛细胞损伤,同时磷酸化的JNK标志着JNK途径的活化,提示JNK途径在细胞凋亡过程中发挥了一定作用。

Apoptosis and its molecular mechanism in vestibular hair cell after gentamycin toxicity

OBJECTIVE: To investigate the character of damaged vestibular hair cells caused by gentamycin, and to identify whether apoptosis and phosphoralation of JNK occurs in the damaged cells. METHOD: Healthy guinea pigs were divided into experimental group and control group randomly with 15 in each group, animals in experimental and control group received systemic injection of gentamycin [100 mg/(kg x d)] and saline respectively for 7 consequent days. All the animals were sacrificed on the 8th day, the crista vestibular of each were observed by preparation and frozen dissection. The apoptosis of hair cell were detected by TUNEL method and phosphoralation of JNK were detected by immunochemistry. RESULT: The lesion and apoptosis of hair cells could be seen in the experimental group,and the phosphoralation could be observed too; the hair cells of control group showed no sign of apoptosis or phosphoralation of JNK. CONCLUSION: Gentamycin cause vestibular hair lesion by inducing apoptosis and activation of JNK plays an important role in the procedure of apoptosis.