褪黑素对乙醇致小鼠慢性肝损伤的保护作用

目的:探讨褪黑素(MT)对实验性慢性乙醇肝损伤小鼠脂质过氧化、肝功能和肝脏病理组织的影响.方法:将48只小鼠随机分为4组:对照组(A组),模型组(B组),造模 高浓度MT给药组(C组),造模 低浓度MT给药组(D组).用60 mL/L乙醇制成小鼠慢性肝损伤模型,测定肝组织中丙二醛(MDA)含量、天冬氨酸转氨酶(AST)和丙氨酸转氨酶(ALT)的活性,切片观察肝脏病理损害程度并评分.结果:MT使慢性乙醇慢性肝损伤小鼠的MDA含量明显下降,有效降低AST和ALT活性,并与剂量呈正相关.MDA:造模 高浓度MT给药组和造模 低浓度MT给药组值均明显较模型组减低(P均＜0.05).ALT:造模 低浓度MT给药组活性值明显低于模型组(P＜0.01);造模 高浓度MT给药组活性值明显较造模 低浓度MT给药组减低(P＜0.01).AST:造模 低浓度MT给药组活性值明显低于模型组(P＜0.01);造模 高浓度MT给药组活性值明显较造模 低浓度MT给药组减低(P＜0.01).病理学形态观察显示,MT能减轻肝脏病理损害程度,与剂量成正相关.病理损害程度评分:造模 低浓度MT给药组值明显低于模型组(P＜0.01);造模 高浓度MT给药组值明显较造模 低浓度MT给药组低(P＜0.01).结论:MT对慢性乙醇肝损伤具有一定的保护作用,且与药物剂量呈正相关.

Hepatoprotective effect of melatonin on chronically ethanol-treated mice

AIM: To investigate the changes of alanine aminotransferase(ALT),aspartate aminotransferase(AST),malondialdehyde(MDA) and pathological lesions of mice livers,which were caused by chronic alcohol drinking,and the protective effect of melatonin(MT) against ethanol-induced chronic hepatotoxicity.METHODS: Forty-eight mice were randomly divided into 4 groups: control group(A),alcohol group(B),alcohol +high dosage MT group(C),and alcohol+low dosage MT group(D).60 mL/L alcohol was used to induce hepatotoxicity in these mice.MT was injected at 20 and 5 mg/kg immediately after alcohol drinking in group C and group D respectively.The activities of ALT,AST and the levels of MDA in liver homogenate were(detected.) And pathological lesion in liver tissue was evaluated.(RESULTS:) MT inhibited the increasing tread of MDA in liver homogenate and lowered the levels of ALT and AST in chronically ethanol-treated mice.MDA: the content in group D and C was lower than that of group B(P<0.05);ALT: the activity in group D was lower than that of group B(P<0.01),and the activity in group C was lower than that of group D(P<(0.01);) AST: the activity in group D was lower than that of group B(P<0.01);the activity in group C was lower than that of group D(P<(0.01).) And in morphology MT could greatly prevent the lesions of chronically ethanol-treated mice livers.Total pathological score: the score of group D was much lower than that of group B(P<0.01);the score of group C was greatly lower than that of group D(P<0.01).CONCLUSION: MT indeed hasa protective effect on chronic ethanol-induced mice livers,which ispositively associated with MT dosage.