蛋氨酸对兔同型半胱氨酸水平及动脉粥样硬化的影响

Effects of excessive methionine diets on the level of total plasma homocysteine and arterosclersis in rabbits

目的 观察高蛋氨酸摄入对实验动物同型半胱氨酸 (Homocysteine Hcy)水平及动脉组织的影响。方法 雄性新西兰兔 2 0只随机分成 2组 :对照组和蛋氨酸组 ,每组 10只 ,分别喂以普通兔饲料及普通兔饲料中添加 0 .5 %的蛋氨酸 ,喂养 6个月后 ,测定血浆 Hcy、血栓烷 B2 (TXB2 )、6 -酮 -前列腺素 F1α(6 - Keto- PGF1α)水平 ,光镜检测主动脉组织学改变。结果 实验后 ,蛋氨酸组断食 2 h和 7h的血浆 Hcy浓度 (分别为 2 36 .5± 5 9.75μmol/ L ,6 7.83± 2 2 .17μm ol/ L )均明显高于对照组 (分别为 10 .6 2± 1.4 2μm ol/ L ,11.0 6± 1.2 3μmol/ L ) ,(P<0 .0 0 1) ;蛋氨酸组主动脉出现典型的动脉粥样硬化损伤 ;血浆 TXB2 水平和 TXB2 / 6 - Keto- PGF1α升高。结论 过量蛋氨酸摄入可引发高 Hcy血症 。

Objective To observe the effects of excessive Methionine(Met) diets on the levels of total plasma homocysteine and arterosclerosis in experimental animals. MethodsTwenty male New Zealand white rabbits were randomly divided into two groups:control group(CG) and Met group (MG),which were fed with a standard rabbit diet and a standard rabbit diet supplemented with 0.5% Met respectively for six months.The levels of total plasma Hcy, thromboxane B2(TXB2),6 ketone prostaglandin(6 Keto PGF 1α ) were measured.The histological changes of aortas were examined by light microscope. Results After experiment, the levels of total plasma Hcy at 2h(236.5±59.75μmol/L) and 7h(67.83±22.17μmol/L) after the cessation of diet in MG were higher than those (10.62±1.42μmol/L, 11.06±1.23μmol/L) in CG ( P <0.001).There were arterosclerosis changes of aortas in MG, and the levels of plasma TXB 2 and TXB 2/6 Keto PGF 1α in MG increased significantly. Conclusion Ingestion of excessive Met may induce hyperhomocysteinemia and aortic arterosclerosis.One of the mechanisms in arterosclerosis induced by hyperhomocysteinemia may be related with the increase of procoagulant activity.