门静脉高压症大鼠肠系膜组织内皮素B受体表达的变化

Expression of Endothelin-B Receptor in the Mesentery of Portal Hypertension Rats

目的:探讨胆汁性肝纤维化引起的门静脉高压症(PHT)大鼠肠系膜组织内皮素B受体表达(ETBR)的变化。方法:取体重250±10g左右的清洁级SD雄性大鼠30只,根据体重随机分为假手术组、模型组,模型制作采用胆总管结扎的方法造成大鼠胆汁性肝纤维化。术后2周和4周分别测定各组的门静脉压力,应用免疫组化和免疫印迹的方法观察肠系膜组织ETBR的表达。结果:术后2周和4周模型组门静脉压力显著升高,分别为11.89±1.38mmHg和16.34±1.63mmHg。免疫组化显示假手术组肠系膜组织ETBR主要见于细动脉内皮细胞,而模型组大鼠ETBR的表达不仅见于细动脉内皮细胞,细动脉平滑肌细胞和微动脉表达也很显著。免疫印迹发现假手术组肠系膜组织ETBR含量很少,模型组大鼠ETBR表达明显增多。结论:正常大鼠肠系膜血管组织ETBR表达较少,随着肝组织损伤加剧和PHT形成,肠系膜组织ETBR表达明显增加,可能参与胆汁性肝硬化PHT形成过程。

Objective： To investigate the expression of endothelin B receptor （ETBR） in the mesentery of portal hypertension （PHT） rats induced by common-bile duct ligation. Methods： 30 Male SD rats （ 240-260 g） were divided randomly into sham group and model group according to body weight. PHT was induced by common bile duct ligation （CBDL） in rats. After 2 and 4 weeks,the portal pressure of each group was measured, and changes of ETBR expression in mesentery was detected by immunohistochemistry and West- ern blotting method. Results： After 2 and 4 weeks, portal pressure of model rats increased significantly, 11.89±1.38mmHg and 16.34±1.63mmHg respectively. Immunohistochemistry showed that ETBR was mainly expressed in the larger arteries of Sham rats＇ mesentery; while in the model rats, ETBR was not only found in the main artery, but also in the microcirculation significantly. Westem blotting found ETBR expression was less in sham group, but it increased significantly in model rats. Conclusions： After 2 and 4 weeks, portal pressure of CBDL rats increased significantly. The mesentery of sham rats expressed less ETBR. With liver damage and PHT formation, the ETBR expression increased obviously.