【摘要】 目的 观察大鼠肝脏缺血再灌注后肝窦内皮细胞凋亡及异丙酚对肝脏细胞凋亡的影响。方法 选用健康SD雄性大鼠24只,随机分为三组(n=8):A组,肝脏缺血30 min再灌注6 h,再灌注即刻从股静脉输入生理盐水10ml·kg-1·h-1 60 min;B组,再灌注即刻静脉注射异丙酚20 mg/kg,继之输入5％异丙酚50 mg·kg-1·h-1 h;C组,给予假手术处理,未予缺血,余处理同A组。再灌注6 h后取肝组织标本行病理组织学观察,同时测定血浆ALT活性和肝组织MDA含量的变化。采用DNA琼脂糖凝胶电泳、TUNEL染色观察细胞凋亡的情况。结果与C组相比,A组凋亡的肝细胞和肝窦内皮细胞明显增加,且凋亡的细胞主要是肝窦内皮细胞,肝细胞凋亡和坏死则较少。与A组相比,再灌注6 h B组TUNEL阳性肝细胞和肝窦内皮细胞数明显减少(p<0.01),肝组织DNA片段形成也明显减少。同时,B组肝组织坏死程度、血浆ALT活性和肝组织MDA含量均明显低于A组(JD<0.01)。电镜显示B组肝细胞和肝窦内皮细胞损伤也明显轻于A组。结论 细胞凋亡是再灌注早期肝脏细胞死亡的重要机制,肝窦内皮细胞凋亡是再灌注早期肝脏细胞死亡的主要特征。异丙酚可以减少再灌注后的肝脏细胞凋亡和坏死,其抗氧化作用是其减少再灌注后的肝脏细胞凋亡的机制。更多还原

【Abstract】 Objective To investigate the sinusoidal endothelia) cell (SEC) apoptosis induced by hepatic ischemia-reperfusion (I/R) and the effect of propofol on the hepatic cell apoptosis in vivo. Methods For hepatic I/R study we utilized a rat model of 70% liver ischemia according to Kohli, et al . Twenty-four male SD rats weighing 250-350 g were randomly assigned to 3 equal groups of eight animals : group A was subjected to 30 min of liver ischemia followed by 6 h of reperfusion and normal saline was infused iv at the onset of reperfusion, at a rate 10 ml · kg-1 · h -1 for 60 min; group B was subjected to the same J/ R as in group A but instead of NS propofol 20 mg " kg was given iv followed by continuous infusion of 0.5% propofol at 50 mg· kg-1 · h-1 for 60 min; group C underwent sham operation followed by intravenous NS infusion at 10 ml kg h for 60 min. Blood samples and liver biopsies were obtained at the end of 6h of reperfusion, for determination of plasma alanine aminotransferase (ALT) activity and hepatic malondialdehyde (MDA) content, apoptosis and microscopic examination (light and electron microscopy) . Apoptosis was determined both qualitatively and quantitatively by DNA laddering and TUNEL methods. Results In group A there was a significant increase in apoptotic hepatocytes and SEC after I/R as compared with group C ( P < 0.01 ) . Most of TUNEL positive cells were SEC and only a small number of hepatocytes underwent necrosis and apoptosis. In group B the number of TUNEL-positive SEC and hepatocytes was significantly smaller than that in group A ( P < 0.01 ) and formation of hepatic DNA fragmentation was also greatly reduced. The degree oi hepatic necrosis, plasma ALT activity and liver MDA content decreased significantly in group B as compared with those in group A ( P < 0.01 ) . Electron microscopic examination showed that both SEC and hepatocyte injuries were much slighter in group B than those in group A. Conclusion Apoptosis is the key mechanism of hepatic cell death in the early stage of reperfusion.characterized by apoptosis of SEC.Propofolinhibits not only hepatocyte necrosis but also SEC and hepatocyte apoptosis after I/R through its antioxidant effect.更多还原