实验性肝硬化中Leptin及其受体的检测与表达意义

目的观察Leptin在实验性肝硬化大鼠血清水平及其受体在肝脏免疫组化表达和定位情况,探讨Leptin及其受体在实验性肝硬化发生病理机制中的作用.方法采用硫代乙酰胺(thioacetamide,TAA)腹腔注射诱导肝硬化动物模型,同时设立正常对照组;测量大鼠体长、体重、Lee'指数,分别测定血清血脂水平;采用酶联免疫分析法(enzyme linked immunosorbant assay,ELISA)检测血清Leptin含量;免疫组化与计算机图像分析技术观察Leptin受体在肝硬化组、正常对照组的表达和定位特点;各组间进行统计学分析.结果肝硬化动物模型复制成功.肝硬化组血清Leptin增高,与对照组比较差异有非常显著性(t=4.338,P＜0.01);肝硬化组Leptin受体表达增高,与正常组比较差异有非常显著性(t=8.104,P＜0.01);肝硬化组血清Leptin水平与胆固醇(TC)正相关(r=0.918,P＜0.05).肝硬化组血清Leptin水平与Leptin受体灰度值呈负相关(r=0.-0.80,P＜0.01).结论Leptin受体在肝硬化的肝脏中表达异常升高,尤其见于再生的肝细胞及窦内皮细胞等,提示Leptin参与肝纤维化的发生.

The detections and significance of Leptin and its receptors in experimentalhepatic cirrhosis

Objective To observe the changes of serum leptin,the expression of the leptin receptors in the liver of experimental hepatic cirrhosis,and to discuss the possible mechanism and significance. Methods Cirrhosis was made by injection of thioacetamide(TAA),and control group was made at the same time.The rats' height and weight, Lee's index were measured during the experiment.The serum fatty acid was measured. The levels of leptin were measured by ELISA.The expression degree and location of leptin receptors were observed by immunohistochemistry stain and measured by image analysis system. Results Hepatic cirrhosis models were successfully constructed. Serum leptin of hepatic cirrhosis group significantly increased compared with control group(t=4.338,P<0.01).Leptin receptors in cirrhosis significantly increased compared with contol group(t=8.104,P<0.01).the serum leptin was closely relevant to TC in hepatic cirrhosis group(r=0.918, P<0.05).The serum leptin was closely negative relevant to gray level of leptin receptors in hepatic cirrhosis group(r=0.918, P<0.05). Conclusion Leptin receptors significantly increased in hepatic cirrhosis,and obviously expressed in liver cells regeneration and sinusoidal endothelial cells.These observations proved leptin appear to promote profibrogenic responses in the liver.