水通道蛋白-1 在肝硬化腹水大鼠腹膜上的表达

目的探讨腹膜上水通道蛋白-1(AQP-1)的表达与肝硬化大鼠腹水形成之间的相互关系.方法 32只健康SD大鼠分为肝硬化组(20只)和正常对照组(12只),采用苯巴比妥钠诱导加皮下注射CCl4制造细胞毒性肝硬化大鼠伴腹水模型;免疫组织化学检测 AQP-1 在大鼠腹膜上的分布及蛋白质的表达.RT-PCR方法检测各组大鼠AQP-1在肝硬化腹水形成前后腹膜上 mRNA的表达,并以3-磷酸甘油醛脱氢酶相对定量.结果腹膜免疫组化显示,AQP-1 主要表达在腹膜毛细血管及小静脉的内皮细胞上,同时,间皮细胞上也有 AQP-1 的表达.在肝硬化早期(第6周末)两组AQP-1蛋白质[相对积分光密度正常对照组(23±10),肝硬化组(21±13)]和 mRNA[正常对照组(0.63±0.11) μg/μl,肝硬化组(0.67±0.15) μg/μl]的表达量差异均无统计学意义.在肝硬化晚期 (第12周末)AQP-1 蛋白质[相对积分光密度正常对照组(23±9),肝硬化组(15±8)]和 mRNA[正常对照组(0.58±0.15) μg/μl,肝硬化组(0.43±0.16) μg/μl]的表达均下调. 结论在肝硬化伴腹水模型大鼠腹膜的毛细血管及小静脉的内皮细胞上AQP-1表达减少, AQP-1 的减少可能参与了腹水的形成.

Expressions of aquaporin-1 on peritonea in hepatic cirrhotic rats with ascites

OBJECTIVE: To investigate the changes of aquaporin (AQP-1) expressions on peritonea in liver cirrhotic rats with ascites, and to study the correlation between AQP-1 expressions and ascites form. METHODS: 32 healthy Sprague-Dawley (SD) rats were divided into two groups randomly, 20 rats were used to produce liver cirrhotic models induced with phenobarbitol sodium and CCl(4). The distribution and protein expressions of AQP-1 on the rats' peritonea were measured with immunohistochemistry assay, and the expressions of APQ-1 mRNA were tested with relative GAPDH quantitative RT-PCR. RESULTS: (1) The expressions of AQP-1 were mainly on the endothelial cells of capillary vessels and venules on the rats' peritonea, and also on mesothelial cells. (2) There was no statistically significant difference between the expressions of AQP-1 protein and mRNA in the two groups on the early stage of liver cirrhosis. (3) Downregulations of the expressions of AQP-1 protein and mRNA were observed in B group on the advanced cirrhotic stage. CONCLUSION: Expressions of AQP-1 were downregulated on the peritonea of rats with decompensated liver cirrhosis, which may play a role in the formation of ascites. The changes of AQP-1 Expressions on peritoneal mesothelial cells which were fewer than those on the endothelial cells may be few relations to ascites form.