茶多酚抗动脉粥样硬化机制研究

目的　观察茶多酚在高脂饲料诱发家兔动脉粥样硬化过程中各种抗氧化和氧化指标的动态变化。方法　选取 1 5～ 2 0kg的家兔 2 4只 ,随机分为 4组 :正常对照组、动脉粥样硬化模型组、低剂量茶多酚组和高剂量茶多酚组。分别于实验前、6周末和 12周末测定血清谷胱甘肽过氧化物酶 (GSH -Px)、红细胞超氧化物歧化酶 (RBC -SOD)活性和血清丙二醛 (MDA)含量。 12周末空气栓塞处死家兔 ,迅速剥离主动脉弓 ,进行病理学检查。结果　动脉粥样硬化模型组家兔血清MDA升高 ,GSH -Px、RBC -SOD活性下降 ,主动脉弓内膜下充满泡沫细胞和粥样斑块 ;而茶多酚能降低血清中MDA含量 (P <0 0 5 ) ,诱导家兔体内GSH -Px、RBC -SOD活性增强 (P <0 0 5 ) ,在一定程度上减轻高脂饲料诱发的家兔动脉粥样硬化程度。结论　抗氧化活性可能是茶多酚预防和改善动脉粥样硬化作用的重要机制之一。

Study on mechanism of green tea polyphenols on anti-atherosclerosis

Objective To study the antioxidation of green tea polyphenols(GTP) on experimental atherosclerosis rabbits fed with high-fat forage. Methods 24 rabbits weighted 1.5-2.0?kg were divided randomly into 4 groups:normal control,atherosclerosis model,low-dose GTP and high-dose GTP groups.The rabbits of control group were fed with basic forage,while others with high-fat forage.The rabbits in low,high GTP groups drank water containing of 0.2% and 0.4% GTP respectively,rabbits in other two groups drank tap water.The blood samples were collected by intracardiac puncture at 1 week and 6,12 weekends respectively and the serum GSH-Px,RBC-SOD activities,serum malondialdehyde(MDA) level were examined.At the end of 12 week,the rabbits were killed by air embolism,peeled off arcus aortae to make pathologic exam. Results The serum of MDA in atherosclerois model increased evidently,while the activities of GSH-Px,RBC-SOD decreased,foam cells and atherosclerotic lesions in arcus aortae were also observed in rabbits of atherosclerosis model group.After treating GTP,the activities of GSH-Px,RBC-SOD enhanced and the MDA level declined significantly(P<0.05),along with the lessening of atherogenesis in some extent. Conclusion GTP may have favorable effects on ameliorating atherosclerosis by its antioxidation.