LXR mRNA在动脉粥样硬化兔中的表达变化

摘要

Objective To observe the expression of LXR mRNA in different stage of the atherosclerosis rab-bits, and investigate the effect of LXR on atherosclerosis. Methods Using randomized controlled method, 20 healthy New Zealand male rabbits were equally allocated into control group and atherosclerosis (AS) group. The control group rabbits were fed with common diet, and the AS group rabbits were fed with a high fat diet and injected with bovine se-rum albumin. Cholesterol (TC), triglyceride (TG), low density lipoprotein (LDL-C), high density lipoprotein (HDL-C), LXR mRNA and electron microscopic observation of external iliac artery in the two groups at the first and the 8th week were detected. Results For blood lipid:At the first week, the TC significantly increased (P<0.05) and HDL-C signifi-cantly reduced (P<0.05) in AS group;At the 8th week, the TC and LDL-C significantly increased (P<0.05) in AS group. In morphology of external iliac artery intima, macroscopic observation at the first week of both groups and the 8th week of the control group were level 0, but level 0.5 at the 8th week in AS group. In electron microscope inspection, there were no obvious pathological changes at the first week of both groups and the 8th week in the control group. At the 8th week, a large amount of fat drops of vesicles, cholesterol crystal sample material, and dense body and mitochondria structure, etc. were visible in the smooth muscle cells in AS group. For LXR mRNA:At the first week, there was no difference be-tween two groups in the expression of LXRαmRNA (P>0.05), while at the 8th week, the expression of LXRαmRNA in the AS group significantly increased (P<0.05). Conclusion Increased expression of LXRαmRNA may be a compensa-tory adjustment mechanism to improve AS in the early stage.%目的：观察LXR mRNA在动脉粥样硬化(AS)兔不同时段的表达，探讨LXR对AS的影响。方法采用随机对照研究的方法将20只健康雄性新西兰兔分为对照组和AS组，各10只，对照组予普通饲养，AS组予高脂饲养并注射牛血清白蛋白。分别在第1周和第8周检测两组兔子胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白(LDL-C)、高密度脂蛋白(HDL-C)、LXR mRNA及髂外动脉组织电镜检测。结果血脂方面，第1周，AS组TC升高， HDL-C降低，与对照组比较差异均有统计学意义(P<0.05)；第8周，AS组TC、LDL-C均升高，与对照组比较差异均有统计学意义(P<0.05)；髂外动脉内膜形态学方面，AS组第1周和对照组第1、8周肉眼观察0级。第8周AS组肉眼观察0.5级；髂外动脉内膜组织电镜检测方面，AS组第1周和对照组第1、8周未见明显病理改变。AS组第8周可见平滑肌细胞中充满了大量脂滴小泡，胞浆中可见胆固醇结晶样物质、密体和线粒体等结构；LXR mRNA表达方面，第1周，LXRαmRNA组间比较差异无统计学意义(P>0.05)；第8周，AS组LXRαmRNA升高，差异有统计学意义(P<0.05)。结论 LXRαmRNA表达升高可能是一种改善动脉粥样硬化早期的代偿调节机制。