甲硫氨酸诱发家兔高同型半胱氨酸血症促进LDL氧化修饰

目的:探讨甲硫氨酸诱发家兔高同型半胱氨酸血症与LDL氧化修饰的关系。方法:将家兔32只随机分为甲硫氨酸(M)组9只,胆固醇(Ch)组9只,甲硫氨酸+胆固醇(M+Ch)组9只和对照(C)组5只。M、Ch和M+Ch组每日先分别喂予含3%甲硫氨酸、3.75%胆固醇和3%甲硫氨酸+3.75%胆固醇的饲料20g后,再自由进食与C组一样的饲料。16周末,心脏穿刺取血测有关指标。结果:①M、M+Ch组血清同型半胱氨酸、ox-LDL和TBARS显著高于C组和Ch组(P＜0.01);②同型半胱氨酸体外诱发LDL氧化修饰随LDL和同型半胱氨酸浓度的增高而增加(P＜0.01)。结论:甲硫氨酸诱发的高同型半胱氨酸血症具有促进脂质过氧化和LDL氧化修饰的作用。

Oxidative modification of low density lipoprotein induced by hyperhomocysteinaemia following application of methionine

AIM: To observe the oxidative modification of low density lipoprotein iinduced by hyper homocysteinaemia following application of methionine. METHODS: Thirty two rabbits were randomized as group methionine(group M, n =9), group cholesterol (group Ch, n= 9), group methionin+cholesterol (group M+Ch, n= 9) and control group (group C, n= 5).In group M, Ch and M+Ch, the animals were fed with the food containing 3% methionine, 3.75% cholesterol and 3% methionine+3.75% cholesterol, respectively. By the end of sixteen weeks, the blood were taken and the measurements were carried out. RESULTS: Following application of methionine, the levels of hyperhomocysteine, ox-LDL and TBARS in group M and group M+Ch were significntly higher than those of group C and group Ch ( P< 0.01). The oxidative modification of low density lipoprotein induced by homocysteine in vitro were significantly increased with the concentrations of LDL and homocysteine ( P< 0.01). CONCLUSION: Those results indicated that hyperhomocysteinaemia induced by application of methionine could promote peroxidation of lipid and oxidative modification of low density lipoprotein.