z-VAD-fmk对烫伤大鼠肾脏细胞凋亡的影响

Effects of z-VAD-fmk on apoptosis in rats kidneys after scald

目的探讨广谱半胱天冬氨酸蛋白酶(Caspase)抑制剂z-VAD-fmk对烫伤大鼠肾脏细胞凋亡的影响。方法 48只雄性Wistar大鼠制作严重烫伤模型并随机分为治疗组与对照组各24只。z-VAD-fmk首次剂量3 mg/kg,此后每隔12 h腹腔注射1.5 mg/kg;对照组用等剂量生理盐水干预。两组分别于造模后2、8、24、48 h各处死6只大鼠,取出肾脏。采用TUNEL法检测肾脏细胞凋亡指数(AI),免疫组化法检测B淋巴细胞瘤/白血病-2(bcl-2)和Bcl-2同源拮抗蛋白/致死蛋白(Bax)表达,荧光比色法检测Caspase-3活性。结果与对照组比较,治疗组造模8、24、48 h AI水平降低、Bax表达水平降低、Bcl-2表达水平升高(P均<0.05)。两组Caspase-3活性均于伤后8 h达峰值;与对照组比较,治疗组造模2、8、24、48 h Caspase-3活性均降低(P均<0.05)。结论 z-VAD-fmk可抑制烫伤大鼠早期肾脏细胞的凋亡,其作用机制可能为下调AI、Bcl-2表达水平、Caspase-3活性,上调Bax表达。

Objective To observe effects of z-VAD-fmk on apoptosis in rats kidneys after scald .Methods Forty-eight rats were randomly assigned into control group （n=24） and treatment group（n=24）.The two groups were made the severe scald model For the treatment group , z-VAD-fmk were administrated immediately at the doze of 3 mg/kg by caudal vein injection and 1.5mg/kg, per 12 h by intraperitoneal injection .The control group was given 0.9%saline instead of z-VAD-fmk with the same method .The two groups were injected sodium lactate ringer ’ s injection after scald according to the formula of Parkland and sodium lactate ringer’s injection was reduced correspondingly .Six rats were killed at 2 h, 8 h, 24 h, 48 h in each group and the kidneys were immediately removed respectively at each time point mentioned above .The detection of apoptotic renal cells was carried out using TUNEL .The expression of Bcl-2 and Bax were observed by immunohistochemical method and activity of caspase-3 were measured with colorimetric chromatometry and .Results Compared with control group, the AI and expression of Bax decreased and Bcl-2 increased in treatment group at 8 h, 24 h, 48h and had statistical differences（P〈0.01） .Caspase-3 activity decreased at 2 h, 8 h, 24 h, 48 h and had statistical differences（P〈0.01）.Conclusion The early application of z-VAD-fmk could effectively reduce renal cell apoptosis and relieve kidney damage.