高密度及低密度脂蛋白受体在兔胆囊结石成石中的变化及意义

CHANGES OF HDL RECEPTOR AND LDL RECEPTOR ACTIVITY OF HEPATOCYTES DURING CHOLESTEROL GALLSTONE FORMATION IN RABBIT MODEL

目的 从脂蛋白代谢的分子受体水平探讨胆囊胆固醇结石的成因。方法 采用高胆固醇膳食 (HCD)诱发兔胆囊胆固醇结石模型 ,动态观测成石过程中高密度脂蛋白受体 (HDLR )及低密度脂蛋白受体 (LDLR)活性变化。结果 进食HCD 1周时肝细胞HDLR活性明显升高 ,而LDLR活性轻微升高 ,随后HDLR及LDLR活性均明显下降 ;血总胆固醇、LDL胆固醇、肝脏及胆汁胆固醇随进食HCD的时间增加而逐渐增高 ,胆汁中胆汁酸则逐渐降低。结论 肝细胞HDLR及LDLR活性变化对胆汁中胆固醇的分泌影响不明显 ,肝细胞HDLR及LDLR活性下降均可引起肝细胞摄取用于胆汁酸合成的底物减少 。

Objective In order to study the mechanism of cholesterol gallstone formation through rabbit model which was induced by high cholesterol diet (HCD), the activities of the high density lipoprotein receptor (HDLR) and low density lipoprotein receptor (LDLR) of hepatocytes were investigated. Results The results were as follows: The HDLR activity increased significantly after taking HCD for one week, at the same time, the LDLR activity only increased slightly. Thereafter, the activities of HDLR and LDLR all decreased markedly. As the time of animals taking HCD went on, serum total cholesterol, LDL cholesterol and hepatic cholesterol increased, but bile acids of biliary tract decreased gradually.Conclusion The results suggest that the changes of HDLR and LDLR activities of hepatocytes had no significant effect on bile cholesterol and the decreased HDLR and LDLR activities may cause the reduction some of substrate for bile acids synthesise and play an important role in the formation of gallstone.