褪黑素对大鼠肝脏缺血再灌注损伤的保护作用

目的 探讨褪黑素对大鼠肝缺血再灌注损伤的保护作用及其机制。方法 将72只6—7周龄的健康雄性Wistar大鼠，随机分为3组，即褪黑素处理组（Mel组）、酒精溶媒对照组（Ale组）、生理盐水对照组（NS组）。建立肝缺血再灌注损伤模型，于不同时点用TBA法和黄嘌呤氧化酶法分别测定肝组织丙二醛（MDA）及超氧化物歧化酶（SOD）含量，免疫组织化学方法检测分析核因子-kB（NF-kB）的表达情况，结果MDA含量在再灌注后各时点的Mel组均显著低于Ale及NS对照组（P〈0．05），SOD含量在再灌注后3h、12h、24h时点的Mel组显著高于Ale及NS对照组（P〈0．05）；Mel组再灌注后各时点的NF-kB蛋白表达阳性率均显著低于Ale组和NS组（P〈0．05）。以上各项指标在各时点Alc组与NS组相比无显著性差异。结论 Mel抗氧化及抑制肝细胞NF—kB的表扶，可能是大鼠肝缺血再灌注损伤的保护作用机制之一。

Protective Effect of Melatonin on Rat Hepatic Ischemia Reperfusion Injury

Objective To explore the protective effect and mechanism of melatonin (Mel) on rat's hepatic ischemia-reperfusion injury. Methods 72 healthy male Wistar rats (6-7 weeks old ) were randomly divided into 3 groups: Mel treated group (Mel), alcohol solvent control group (Alc) and saline control group (NS). To establish partial hepatic ischemia-reperfusion injury models, malonaldehyde(MDA),superoxide dismutase (SOD)were examined by TBA method and xanthinoxidase method respectively,immunohistochemistry stainning was used to detect the expression of naclear factor (NF-κB). Results The level of MDA in Mel group was significantly lower than that in the Alc and NS groups (P<0.05), the level of SOD of Mel group measured in 3h, 12h, 24h after reperfusion was significantly higher than that in Alc and NS groups (P<0.05). The expression of NF-κB in Mel group markedly lower than that in Alc and NS groups (P<0.05). Without significant differences between Alc and NS group. Conclusion The inhibition of the expression of NF-κB by Mel may be one of the mechanisms for the protective effect of Mel on hepatic ischemia-reperfusion injury .