急性胆道感染诱发凋亡相关基因表达的实验研究

Study of apoptosis-related gene expression induced by acute biliary infection

目的：研究急性感染过程中是否存在肝细胞凋亡，并探讨肝细胞凋亡的可能机制。方法研究于2013年9至10月在烟台毓璜顶医院中心实验室进行。30只实验大鼠适应喂养7 d后随机分为5组，其中1组为对照组，余下4组为实验组，实验组通过胆总管注入大肠埃希菌，建立急性胆道感染模型，并于注入大肠埃希菌6、12、24及48 h后处死。对照组动物胆总管内注入1 ml生理盐水，6 h后处死。取各组肝组织，制作切片。TUNNEL染色，计数凋亡肝细胞；免疫组织化学试验检测BCL-2、BAX的表达。结果各实验组与对照组相比，TUNNEL染色阳性肝细胞表达差异有统计学意义（P〈0.05），24 h和48 h组TUNNEL染色阳性表达较6 h组与12 h组明显增加（P〈0.05）。对照组与实验组间BAX表达差异有统计学意义（P〈0.05），随着时间延长表现出逐渐增多的趋势，但变化差异无统计学意义（P〉0.05）。而BCL-2在对照组和6 h实验组间没有体现出明显差异，但随着时间的延长，以12 h与24 h组为界，实验组前后间的BCL-2表达出现显著差异。结论急性胆道感染后肝细胞在短时间内即会出现细胞凋亡，并且贯穿于急性胆道感染始终，基因层面表现为促凋亡基因BAX表达增强，抑制凋亡基因BCL-2表达减弱。且TUNNEL所示肝细胞凋亡改变与基因表达改变存在时间上的一致性，表明凋亡基因的改变可能带动了肝细胞凋亡的发生。

Objective To determine whether liver cell apoptosis exist in the process of the acute infection, and to explore the possible mechanism of liver cell apoptosis. Methods 30 experimental rats were fed for 7 days and divided into 5 groups, one of them served as the model group, the other groups as the experimental group. The Escherichia coli were injected into the common bile duct of the four groups to establish the model of acute biliary. The four groups were sacrificed at 6, 12, 24 and 48h after injection of Escherichia coli. Injection of when the control group rats were injected 1 ml saline into the common bile duct and killed after 6h. Made sections with every rat’s’ liver tissue, counted apoptotic hepatocytes and detected the expression of BCL-2, BAX by immunohistochemistry chemical test methods. Results The expressions of the positive hepatocytes were significant differences between the model group and the experimental groups（P〈0.05）, also between 24、48 h and 6、12 h （P〈0.05）.BAX expression, There was a significantly different between the model group and the experimental groups on BAX expression , which gradually increased with time, but no significant difference change（P〉0.05）. There was not a significant difference between the model group and the 6h experimental group on BCL-2 expression, but BCL-2 expression is bounded 12 h and 24 h group, the experimental group between before and after the emergence of a significant difference. Conclusion Hepatocyte apoptosis appears in a short period of acute biliary tract infections, and throughout acute biliary tract infection, the expression on the gene level was to enhance the number of BAX and to decrease BCL-2. Changes in liver cell apoptosis and gene expression were in the consistency of the existence of time, indicating that changes in apoptotic gene led to the liver cell apoptosis.