Caspases在消炎痛所致胃黏膜细胞凋亡中的作用  

Effects of caspases in indomethacin-induced gastric mucosal cell apoptosis

作　　者：崔忠敏[1] 李兆申[2] 湛先保[2] 范群铭[2] 

机构地区：[1]沈阳军区总医院消化内科,沈阳110016 [2]第二军医大学长海医院消化内科

出　　处：《解放军医学杂志》2005年第6期504-506,共3页Medical Journal of Chinese People's Liberation Army

摘　　要：目的研究大鼠在体情况下消炎痛(IND) 所致胃黏膜细胞凋亡过程中caspase-3、-8基因及蛋白表达的变化,以探讨其黏膜损伤机制.方法 SD大鼠以不同剂量IND(30、60、90、120mg/kg)灌胃后3h处死,另设对照组.采用TUNEL标记技术检测黏膜细胞凋亡;分别采用原位分子杂交和RT-PCR检测caspase-3基因表达的变化,应用免疫组化方法同步检测caspase-3、-8蛋白表达的变化.结果 TUNEL标记显示对照组大鼠胃黏膜仅见少量凋亡细胞,IND组凋亡细胞数明显增加,计算机图像分析显示阳性细胞平均像素点在IND 30、60、90、120mg/kg组分别为对照组的6.3、8.0、12.6和17.1倍(P<0.01);原位分子杂交显示,caspase-3 mRNA在对照组胃黏膜呈弱阳性表达,IND 30～90mg/kg组呈中等至强阳性,120mg/kg组呈强阳性表达,与对照组相比均有显著差异(P<0.01), caspase-3 mRNA表达变化同细胞凋亡之间呈明显正相关(r=0.9642,P<0.01);RT-PCR显示对照组胃黏膜中caspase-3 mRNA表达量极少,IND各剂量组的caspase-3/β-actin吸光度比值较对照组明显升高(P<0.01);免疫组化染色显示对照组胃黏膜caspase-3、-8蛋白均呈弱阳性表达,caspase-3表达水平强于caspase-8(P<0.05),IND使caspase-3、-8蛋白表达呈中等至强阳性,明显高于对照组(P<0.05),IND各剂量组caspase-3表达水平均高于caspase-8(P<0.05),caspase-3蛋白表达的变化与其基因表达的变化是同步的,且两种蛋白表达的变化同细胞凋亡之间呈明显正相关(r=0.9473, r=0.9563, P<0.01).结论 IND可在转录和翻译水平上调效应子caspase-3表达,使其前体水平增加,促使其活化,与此同时使启动子caspase-8前体蛋白表达上调并使之活化,进而启动了细胞内的凋亡信号传导通路,导致胃黏膜细胞凋亡.Objective To determine the changes of caspase 3 and 8 genes and protein expressions during indomethacin (IND) induced gastric mucosal cell apoptosis in vivo . Methods Healthy male SD rats were treated intragastrically with four different doses of IND. The rats were killed 3 hours after IND administration and the TUNEL technique was applied to detect mucosal cell apoptosis. The change of caspase 3 mRNA expression was detected by in situ hybridization and RT PCR techniques and the changes of caspase 3, 8 protein expression were monitored immunohistochemically. Results In the rats of control group, TUNEL assay revealed that only a few apoptotic cells. Oral administration of IND resulted in the appearance of massive TUNEL positive cells. Computer aided image analysis showed that the mean pixels in 30~120mg/kg groups were 6 3 , 8 0 , 12 6 and 17 1 fold that in control group ( P <0 01 vs control). In situ hybridization indicated that caspase 3 mRNA was weak positive in control group. IND administration significantly up regulated its expression. The expression in 30~90mg/kg groups was moderate to strong positive, while in 120 mg/kg group, the expression was strong positive, significantly increased compared with that in control group ( P <0 01). The changes of caspase 3 mRNA expression were significantly positive related to cell apoptosis ( r =0 9642, P <0 01). Very few expression of caspase 3 mRNA was detected by RT PCR in the gastric mucosa of control group tats. The intense signals for caspase 3 mRNA were detected after IND administration. Compared with that of control group, the caspase 3/β actin ratios were significantly increased ( P <0 01). The expressions of caspase 3 and 8 protein using immunohistochemistry were weak positive in control group and the expression of caspase 3 was stronger than that of caspase 8 ( P <0 05). Compared with the control group, oral administration of IND markedly intensified the expression of caspase 3 and 8 with the

关 键 词：吲哚美辛 胃黏膜 细胞凋亡 CASPASES 

分 类 号：R573.1[医药卫生—消化系统]