甲硫氨酸诱发家兔高同型半胱氨酸血症促进LDL氧化修饰

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

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 2 0g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 0 1) ;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 0 1)。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。

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.