Study of cells and peptides controling the hepatic sinusoidal blood flow

为了解肝硬变时肝窦微循环的变化，我们进行了以下研究。人正常肝组织和肝硬变组织的研究：与正常肝相比，肝硬变肝窦壁上α-平滑肌肌动蛋白(α-SMA)和内皮素-1受体(ET-1R)的免疫定位显著增加。这些产物主要定位于肝星状细胞(HSCs)。结论：1.与正常肝组织相比，肝硬变组织中的神经末梢和S-100蛋白的免疫定位明显减少。硫代乙酰胺治疗大鼠肝硬变模型的肝脏微循环研究门静脉注射一氧化氮(NO)抑制剂L-NMMA可引起门脉压力升高，门脉血流量和肝血流量下降。体外培养的大鼠肝星状细胞的研究：(1)培养的大鼠肝星状细胞在加入ET-1后收缩，而在IL-1β作用下，随着细胞内NO的升高而松弛。(2)激光共聚焦显微镜观察正常肝、肝硬变和大鼠肝星状细胞中抗α-SMA和抗ET-1R的免疫荧光强度，肝硬化组HSC中这两种抗体的免疫荧光强度较正常组显著增强，提示肝硬变时HSC通过ET-1和NO而不是小叶内神经支配收缩和松弛，参与肝窦微循环。

We performed the following studies to understand the changes of hepatic sinusoidal microcirculation in liver cirrhosis.1. Studies of human normal liver tissues and cirrhotic liver tissues.Immunolocalization of alpha-smooth muscle actin (alpha-SMA) and endothelin-1 receptor (ET-1R) was significantly increased along the sinusoidal walls in cirrhotic liver compared with normal liver. These products were mainly localized in hepatic stellate cells (HSCs). However, nerve endings and immunolocalization of S-100 protein were markedly decreased in cirrhotic liver compared with normal liver.2. Studies of hepatic microcirculation using a thioacetamide treated rat cirrhosis model.The elevation of the portal pressure and the decrease of the portal and hepatic blood flows were induced by the injection of L-NMMA,which is a nitric oxide (NO) inhibitor, in the portal vein.3. In vitro studies using rat cultured HSCs.(1) Cultured rat HSCs contracted in response to the addition of ET-1, and relaxd in response to the elevation of intracellular NO with interluikin-1 beta treatment. Moreover, immunofluorescent intensity of anti-cyclic-GMP in HSCs was significantly increased after IL-1 beta addition compared with before IL-1 beta treatment.(2) Immunofluorescent intensity of anti-alpha-SMA and anti-ET-1R in HSCs obtained from normal liver and cirrhotic liver or rats was examined with a confocal laser-scanning microscope.Immunofluorescent intensity of these antibodies was significantly increased in HSCs of the cirrhosis group compared with the normal group.Based on these results, the contraction and relaxation of HSCs through ET-1 and NO rather than through intralobular innervation are suggested to be deeply involved in hepatic sinusoidal microcirculation in liver cirrhosis.