动脉粥样硬化进程中血脂、血流动力学指标和血管内膜的动态变化

为了建立兔高脂血症及动脉粥样硬化（AS）斑块模型，观察AS斑块形成的动态变化，采用高胆固醇饲料喂养法与免疫反应损伤法结合制备兔高脂血症及AS斑块模型。将45只新西兰兔分成对照组和高脂血症模型组，按照建模时间4、8、12周，又将对照组和模型组分别分为3组。分别于4、8、12周，处死对照组和高脂血症模型组，测定了血脂、血流动力学指标，观察了血管内膜的变化。结果表明：（1）高脂饲养4、8、12周后模型组兔血清中的TC含量显著升高，TG含量在高脂饲养8周开始有明显升高，HDL—C的含量比对照组HDL-C含量要高，但是随造模时间有下降的趋势，LDL—C的含量随造模时间显著升高；（2）血液黏度在高脂模型12周时0．512S^-1和5．96S^-1下，与对照组比较增高显著，颈总动脉血流量和收缩压（BSP）在造模时间8、12周时比对照组有显著增加，而血浆黏度和血管外径随造模时间变化不明显；（3）石蜡切片HE染色，光学显微镜下观察，正常对照组血管内膜光滑，4周模型组内膜有轻微增厚，有少量含脂质的泡沫细胞，8、12周模型组内膜均有明显增厚，并有多层含脂质的泡沫细胞。透射电镜观察，内皮下有沉积形成的脂质空泡。（4）采用免疫组化的方法鉴定了AS斑块处平滑肌细胞源性的泡沫细胞。结果显示：血脂不同组分的变化可以对AS进程起到预示作用；在AS进程中伴随血流动力学因素颈动脉血流量增加、血压升高和低切变率下血液黏度升高；血管内膜不断增厚，AS斑块的成分也会发生变化。

Dynamic Alteration of Blood Lipid and Hemodynamics Parameters and Vascular Intima in the Process of Atherosclerosis

To establish and observe rabbit hyperlipemia and atherosclerosis model, we combined the method of high-lipid diet and immuoreactive injure. We divided 45 New Zealand rabbit into control group and high-lipid group. According to the time (4, 8, 12 weeks) of established model, the control group and high-lipid group were divided into 3 groups respectively. The blood-lipid, the hemodynamics parameter and vascular intima were determined and observed. The results showed: (1) After feeding 4, 8, 12 weeks, TC and LDL-C of the high-lipid group in the serum increased obviously. After feeding 8 week, TG of the high-lipid group began to increase obviously. HDL-C of the high-lipid group was higher than control group, but with a descendent trend. (2) Blood viscosity of the high-lipid group increased obviously under the 0.512 S(-1) and 5.96 S(-1) at 12 week. Blood flow increased obviously at 8 and 12 week. SBP increased evidently at 8 and 12 week. Alteration of the plasma viscosity and vascular diameter were not obvious. (3) By observing with optical microscope the intima of the control group is smooth. The intima of the high-lipid group has a light incrassation at 4 week. The intima of the high-lipid group has a obvious incrassation at 8 and 12 week. By observing with through transmission electron microscopy (TEM), the lipid vacuole is under the endothelium cell. (4) By adopting the immunohistochemistry, the foam cell that derived from smooth muscle cell were determined. We concluded that the blood lipid can have a prefigurative role in atherosclerosis; blood flow and blood pressure and blood viscosity increase at low shear rate in the course of the atherosclerosis; vascular intima is incrassate and the composition of the AS plaque is variational continually.