过氧化物酶Ⅰ、过氧化氢酶、超氧化物歧化酶在大鼠肝缺血再灌注损伤小肠内的表达变化

摘要

Objective: To observe expression change of peroxiredoxin, catalases and superoxide dismutase in the small intestine of rats with hepatic ischemia reperfusion injury, and level of oxidative stress in the small intestine. Methods: The hepatic blood vessel and bile duct leading to both the left and middle hepatic lobes were first clipped and then released thirty minutes later to restore the blood supply so as to establish 70% hepatic ischemia reperfusion injury model of rats. The serum, liver and small intestine tissues were taken 6 hours after the reperfusion. The activities of alanine aminotransferase (ALT) in the serum were detected with full automatic biochemical aualyzer. The malondialdehyde contcnt in the serum and small intestine tissues were determined with thiobarbituric acid colorimetric method. The H2O2 content in the serum and small intestine tissues were detected with spectrophotometric method. The morphological changes of the liver and small intestine were observed under microscope using H-E staining. The expression of peroxiredoxin, catalase and superoxide dismutase mRNA in small intestine tissues was evaluated by RT-PCR and protein level of peroxiredoxin, catalase and superoxide dismutase was estimated by Western blotting. Results: Compared with the control group, the ALT activity and the content of malondialdehyde and H2O2 in the serum of rats with hepatic ischemia reperfusion injury were increased significantly. H-E staing results of hepatic ischemia reperfusion injury group showed that the morphology of the liver was significantly impaired. The content of malondialdehyde and H2O2 in small intestine tissues of the hepatic ischemia reperfusion injury group was higher than that of the control group; the mRNA and protein level of peroxiredoxin, catalase and superoxide dismutase in the small intestine were also increased significantly. Conclusion: Peroxiredoxin, catalase and superoxide dismutase may play a role of anti-oxidative stress when the small intestine is in a state of high oxidative stress.%目的:观察过氧化物酶Ⅰ (PrxⅠ)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)在大鼠肝缺血再灌注损伤模型小肠内的表达变化以及小肠内氧化应激的水平,探讨肝缺血再灌注损伤对小肠的影响及PrxⅠ、CAT、SOD的抗氧化作用.方法:制备大鼠70%肝缺血再灌注损伤模型.肝缺血再灌注6h后取血、肝和小肠.采用全自动生化分析仪测定血清丙氨酸氨基转移酶(ALT)活性;钼酸比色法和硫代巴比妥酸比色法测定血清、小肠中H2O2和丙二醛(MDA)的含量;H-E染色法观察肝、小肠的形态学改变;RT-PCR测定小肠组织PrxⅠ、CAT、SOD mRNA水平的表达,免疫印迹测定其蛋白水平的表达.结果:与对照组相比,肝缺血再灌注损伤组大鼠血清ALT活性、MDA和H2 O2的含量明显升高;H-E染色结果显示模型组大鼠肝组织形态结构受损明显;小肠组织内MDA和H2O2的含量明显高于对照组,PrxⅠ、CAT、SOD的mRNA和蛋白表达水平与对照组相比也升高明显.结论:PrxⅠ、CAT和SOD在小肠组织处于高度氧化应激状态过程中可能发挥了抗氧化应激作用.