Resarch on trial to suppress surgical in cirrhotic liver by modulating activation of hepatic sinusoidal cells.

首先，通过口服硫乙酰胺8周建立肝硬化大鼠模型。在这个模型中，caveolin-1在肝脏中已经被证明具有拮抗eNOS的作用，它被过度表达。在本研究中，我们决定研究HMG-CoA还原酶抑制剂对肝脏缺血/再灌注损伤的影响，因为已有报道称它们可以调节caveolin-1的功能。在我们的实验中，我们使用了普伐他汀。我们检测了普伐他汀对正常大鼠肝脏I/R损伤的影响，但与对照组相比，普伐他汀预处理对肝I/R损伤没有抑制作用。我们还检查了对肝硬化大鼠肝脏的影响。肝硬化患者肝I/R后血清转氨酶水平明显低于正常肝脏。与对照组相比，普伐他汀治疗组I/R损伤有抑制的趋势，但差异不显著。提示肝硬化肝I/R损伤的机制可能不同于正常肝脏。因此，为了阐明正常肝脏和肝硬化肝脏I/R损伤机制的差异，采用DNA阵列技术，以正常大鼠肝脏和肝硬化大鼠肝脏提取mRNA，检测两者之间基因表达的差异。结果表明，与细胞周期和应激蛋白相关的几个基因上调。虽然需要对这些基因进行精确检查，但调节这些基因可能是抑制肝硬化I/R损伤的替代靶点。由于普伐他汀没有显示出对I/R损伤的抑制作用，我们尝试了使用Y-27632 （ROCK/Rho激酶抑制剂）和吡咯烷二硫代氨基甲酸酯（PDTC）的其他方法来操纵窦细胞，这些方法可以诱导肝脏中的血红素氧化酶-1。前者改善了正常大鼠肝脏微循环，抑制了肝I/R损伤和内源性肝损伤；后者对正常大鼠肝窦有扩张作用，抑制了I/R损伤。这些结果表明，调节正弦细胞可能是一种减少肝I/R损伤的新方法，即使在肝硬化中也是如此。我们相信上述结果将为开发新的方法来抑制肝硬化肝窦循环障碍和I/R损伤奠定基础。少

First, we established the cirrhotic rat model by orally administrating thioacetamide for 8 weeks. In this model, caveolin-1, already shown to antagonize eNOS in the liver, was overexpressed. In this research, we decided to examine the effect of HMG-CoA reducase inhibitors on hepatic ischemia/reperfusion injury because they have been reported to modulate the function of caveolin-1. In our experiments, we used pravastatin.We examined the effect of pravastatin on hepatic I/R injury in normal rat liver, but pre-treatment of pravastatin did not suppress the injury compared with the control. We also examined the effect in the cirrhotic rat liver. In the cirrhotic liver, serum transaminase levels after hepatic I/R were much lower than in normal liver. The I/R injury in the pravastatin-treated group tended to be suppressed compare with the control, but it was not significant. The results suggested that the mechanism of hepatic I/R injury in cirrhotic liver might be different from in normal liv … More er.So, to elucidate the difference of mechanism of hepatic I/R injury between normal liver and cirrhotic liver, the difference of the gene expression between them was examined with, DNA array technique using mRNA extracted from normal rat liver and cirrhotic rat liver. The result showed that several genes related with cell cycle and stress proteins were up-regulated. Although the precise examination of those genes is needed, modulating those genes would be alternative targets for suppressing I/R injury in cirrhotic liver.Because pravastatin did not show the suppressive effect on I/R injury, we tried other ways for manupulation of sinusoidal cells using Y-27632, a ROCK/Rho kinase inhibitor, and pyrrolidine dithinocarbamate (PDTC), which induced heme oxygenase-1 in the liver. The former improved hepatic micro-circulation and suppressed hepatic I/R injury in normal rat liver and endotoxic liver injury, and the latter showed dilatative effect of hepatic sinusoids and suppressed I/R injury in normal liver. Those results suggest that modulating sinusoidal cells be a novel possible approach to minimize hepatic I/R injury, even in cirrhotic liver.We believe the results above altogether will be the basis for developing novel approach to suppress the disturbance of sinusoidal circulation and I/R injury in cirrhotic liver. Less