家兔AS模型中血浆脂蛋白水平与主动脉内膜脂纹的相关性分析及病理学观察

目的研究血浆脂蛋白水平变化与主动脉内膜增生程度的相关性,探讨动脉粥样硬化形成的机制。方法以高酯饲料喂养复制家兔实验性动脉粥样硬化(AS)模型,分阶段(0、33、100d)检测家兔血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-c)和低密度脂蛋白胆固醇(LDL-c)水平;观察主动脉内膜病理学变化。测量主动脉内膜厚度并计算其与主动脉直径(AD)的比值(AIT/AD),分析AIT/AD与LDL-c、HDL-c、TC和TG水平的相关性。结果高脂组家兔主动脉内膜脂斑脂纹及粥样灶形成,分别占主动脉内膜总面积的46.20%和22.1%;主动脉内膜平均厚度(AIT)为(1.73±0.79)μm2,占主动脉外径的8.03%,明显比对照组增加(P<0.01)。AIT/AD与血浆TC、LDL-c水平呈显著正相关(r=0.644、0.637,P<0.01),AIT/AD与LDL-c呈极显著回归关系(b=0.06,P<0.01)。结论提示血浆LDL-c水平的升高,是AS发生发展的重要因素。

Studies of correlation between plasma lipids and aortic intimal thickness in experimental AS model of rabbits

Objective] To Study the correlation between plasma lipids and aortic intimal thickness from the experimental model of atherosclerosis (AS) and hyperlipidemia in cholesterol-fed rabbits. Methods] The New Zealand white rabbits were randomized into two groups: AS group and control group. The changes of total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol(HDL-c),low density lipoprotein cholesterol(LDL-c) in serum were detected by stages. The aortic intimal thickness were measured and (aortic intimal thickness/ aortic diameter ) ratio were analysed. Results] It was measured that the areas of aortic intimal hyperplasia and the AS were 46.20% and 22.1% of the total area of the aortic intimal, respectively; the AIT was significantly increased (P <0.01) in AS group compared with the control group. The AIT was positively correlated with the TC and the LDL-c level in serum (r =0.644, 0.637, P <0.01), and multivariate regression analysis revealed that the LDL-c was the more significant variable associated with AIT/AD (b =0.06, P <0.01) compared with either TC or TG. Conclusion] The results suggest that the higher level of plasma LDL-c may be the reason of AS in experimental model of AS and hyperlipidemia in rabbits.