即早基因c-Jun在顺铂诱发豚鼠耳蜗Corti器细胞凋亡中的作用

The Role of C-Jun Associated with in Cisplatin(CDDP) Apoptosis in Guinea Pig Cochlea

目的探讨即早基因c-Jun在耳蜗细胞凋亡中的作用。方法 20只豚鼠随机分为实验组和对照组,每组10只,实验组豚鼠腹腔注射顺铂4mg.kg-1.d-1,连续4天,制备感音神经性聋动物模型,对照组每天腹腔注射等量生理盐水。两组动物耳蜗组织切片后,用HE染色、末端转移酶介导的原位缺口末端标记染色(TUNEL)技术及电镜等观察耳蜗Corti器细胞凋亡状况,用免疫组化染色方法检测正常和凋亡耳蜗Corti器细胞的c-Jun表达情况。结果实验组豚鼠腹腔顺铂注射4天后,耳蜗Corti器的TUNEL阳性细胞数较对照组明显增多(P<0.05),实验组和对照组Corti器细胞c-Jun的平均光密度值分别为0.51±0.08和0.33±0.07,实验组c-Jun的表达高于对照组(P<0.05)。结论耳蜗细胞凋亡时c-Jun蛋白表达增加,表明c-Jun可能参与了耳蜗细胞凋亡的调控,是顺铂导致感音神经性聋的一个重要因素。

Objective To study the role of c-Jun in cisplatin（CDDP） induced apoptosis in cochlear ceils. Methods Twenty guinea pigs were randomly divided into two groups with 10 guinea pigs in each group. The test group animals were injected CDDP in accordance with the dosing 4 mg· kg-1 d-1 intraperitoneally, and the control group animals received an injection of same amount of saline. The apoptosis states in the Corti＇s cell determined by e- lectron microscope and TUNEL method and the immunohistochemical methods were applied to explore the differ- ences of the expression of c--Jun after CDDP were used for 4 days. Results Compared with the control group, the TUNEL--positive cells in the CDDP group significantly increased（P〈0.05）. The expression of c--Jun in CDDP group were significantly higher than that in the normal group（P〈0.05）. Conclusion The results presented a direct morphological evidence for the expression of c--Jun when apoptosis occurred in guinea pig cochlea. The expression of c--Jun participated in the regulatory procedure of apoptosis and may be a possible factor of the etiologies of senso- rineural hearing loss.