肝硬化形成过程中大鼠肝组织结构上H_1、H_2受体的放射自显影研究

An autoradiographic study of H_1 and H_2 receptors in the hepatic tissues of rats with experimental cirrhosis with portal Hypertension

用光学放射自显影术对四氯化碳诱导的大鼠肝硬化形成过程中肝组织结构上的H_1、H_2受体进行定位研究。结果发现,H_1、H_2受体广泛分布于肝细胞和肝内血管壁上;肝硬化形成过程中,肝组织结构上的H_1,H_2受体较对照组显著减少(P<0.05),小叶下肝静脉壁上的H_1受体减少更明显。受体的上述变化可能是四氯化碳对肝细胞的毒性作用和血管壁上的受体发生了"下行调节"的结果。

The histamine H_1 and H_2 re ceptors have been previosly documented in the liver of rat. The present study is aimed at investigating their distributions and change in the bepatic tissues of Wistar rats during the processes of CCl_4-induced cirrhosis by light autoradiography with joining contact method with labeling by H-cimetidine and H-meyrilamine in vitro. The results revealed that the histamine H_1 and H_2 receptors were extensively distributed in the hepatocytes; intrahepatic vascular walls and the hepatocytes containrd more H_1 receptors than H_2 receptor(P<0.01); H_1 receptors in the intrahepatic venous walls were 10 times that in intrahepatic arterial and portal walls(P<0.01). H_2 receptors were fairly well-distributed among various intrahepatic vascular walls (P>0.05); H_1 and H_2 receptors in the hepatocytes and vascular walls decreased markedly in cirrhotic liver tissues (P<0.05); and the number of H_1 receptors in the intrahepatic venous walls was reduced more drastically than H_2 receptor. These results suggested that the abnormalities in both density and distribution of H_1 and H_2 receptors within hepatocytes and various intrahepatic vascular beds may be the consequence of the pathological process of the liver and may have some effects on histamine-mediated hepatic metabolism and splanchnic hemodynamics, which contributes to the pathogenesis of portal hypertension.