胱氨酸致家兔动脉粥样硬化的实验研究

EXPERIMENTAL STUDY ON CYSTINE INDUCED ATHEROSCLEROSIS

本实验用雄性新西兰兔２０只，随机分为胱氨酸实验组和正常对照组，在实验前和喂胱脱氨酸后第１、２、３个月进行血液生化检查。结果发现，实验组血清胱氨酸水平明显增高，血小板聚集功能、血浆凝血烷 Ｂ２（ＴＸＢ２，血栓素Ｂ２）水平也随之增加，而６－酮－ＰＧＦ１。则下降，血清胆固醇无明显变化。经３个月处死动物后病理检查发现实验组兔主动脉壁粥样硬化斑块面积明显高于对照组，主动脉组织内胆固醇含量也显著增高，镜检发现动脉壁有较多泡沫样细胞堆积。这提示高胱氨酸血症可引起显著的动脉粥样硬化，其机制通过破坏动脉内皮，致使血小板功能活化，ＰＧＩ２－ＴＸＡ２失衡，促进脂质在动脉壁沉积，与血脂水平无关。

Twenty New Zealand rabbits were divided randomly into experimental (fed cystine 0. 3 g/day) and control groups. Blood was drawn before and 1, 2 and 3 months after cystine feeding, serum cystine was determined polarimetrically. Comparing with the controls, serum cystine concentration, platelet aggregation, and plasma TXB2 level remarkable increased, but plasma PGI2 decreased in the experimental group,while serum cholesterol level showed no change. After the 3rd month, all of the rabbits were killed. Pathologic examination of the aorta revealed marked atherosclerotic plaques with accumulation of foam cells in the cystine-fed rabbits. Aortic cholesterol content was also remarkablely higher than normal rabbits. It is concluded that hypercystineamia may lead to accelerated atherosclerosis by activated platelet function, and imblance of PGI2-TXA2 without change of blood lipid lev