N乙酰半胱氨酸对肠道缺血再灌注引起肝脏损伤的保护作用

Protective Effect of N-acetylcysteine on Hepatic Damage Induced by Intestinal Ischemic-reperfusion in Rats

N-乙酰-L-半胱氨酸（NAC）是体内游离巯基的组成部分，可补充体内谷胱甘肽，具有清除自由基，保护细胞的作用。本实验观察补给NAC在大鼠肠系膜上动脉夹闭造成缺血再灌损伤时，对肝脏的保护作用。大鼠肠系膜上动脉夹闭45分钟后松夫，于松夹前或后5分钟给予NAC（50mg／kg），测定松夹后2、4、6小时肠、肝组织总流基（TSH），游离巯基（NPSH），丙二醛（MDA）和髓过氧化酶（MPO）的改变。结果给予NAC可明显增加组织NPSH水平，降低MDA和MPO含量．但松夫后给予NAC者效果优于松夫前给予者。说明NAC对缺血再灌注引起的肝脏损伤具有保护作用。

N-acetylcysteine (NAC)is an important part of free thiol in vivo,a precursor for glutathione,and has the functionsof scavenging free radiacals and cell protection- The aim of this study was to explore the effect of NAC on ischemia-reperfued injury of intestinal and liver in a model of superior mesenteric artery occlusion in rats. The superior mesentericartery was occluded for 45min before refease,NAC(50mg/kg) was administrated intravenously 5min preor post -reper-fusion. Tissues were sampled at 2, 4, 6h after reperfusion for determination of contents of total thio1 (TSH),free thiol(NPSH),malondialdehyde (MDA) and activity of myelo-perosidase (MPO). The results showed that NAC coukl increasethe tissue thiol contet and decrease MDA and MPO activity with more potent effect observed in treatment of post reper-fusion. It was suggested that NAC possess protective effect on ischemic-reperfusion induced intestinal and liver injury.