高脂饲料加空气干燥术建立兔颈动脉粥样硬化模型

为建立一种新的比较适合于研究颈动脉粥样硬化的动物模型 ,将 5 4只日本大耳白兔分为 3组 ,分别给予高脂饲料喂养加空气干燥术 (n =2 4)、单纯高脂饲料喂养 (n =2 4)和正常饲料喂养 (n =6 )。在实施空气干燥术后的第 3天、第 1周、第 2周和第 4周时分别处死动物 ,观察颈动脉病变的形态特征 ,计量其内膜增厚程度。结果发现 ,在高脂饲料加空气干燥术组出现较典型的动脉粥样硬化病变 ,包括内皮细胞再生、内膜增厚、平滑肌细胞移行增殖、脂质沉积、弹力纤维和胶原基质的生成等。第 2周和第 4周时内膜增生明显 ,内膜与中膜面积比值分别达到0 .47± 0 .0 7和 0 .94± 0 .0 7,而在单纯高脂饲料组的颈动脉和高脂饲料加空气干燥术组的对侧颈动脉未发现明显的动脉粥样硬化病变。以上结果提示 ,高脂饲料加空气干燥术可以使家兔形成典型的颈动脉粥样硬化病变 ,其病理改变较适合于研究颈动脉粥样硬化。

A Novel Experimental Carotid Atherosclerotic Rabbit Model Induced by High-Cholesterol-Diet Plus Air-Drying

Aim　To establish a new animal model which is more suitable for the study on carotid atherosclerosis and to investigate its mechanisms.　Methods　54 male Japanese White rabbits were randomly divided into 3 groups. The first group was fed by normal diet as blank control (n =6), the second group was fed by high-cholesterol diet as choleste r ol-fed control groups (n=24), the third group was fed by high-cholesterol diet and treated by air-drying as experimental groups ([ W TBX n=24).　Animals were sacrificed at various times (from 3 day s to 4 weeks) after surgery in the experimental groups and at the corresponding times in the control groups.　The carotid arteries were prepared for examination by light microsocopy and by transmission electron microsocopy.　The intimal thickening were evaluated by intimal area/medial area ratio(I/M ra tio).　Results　The typical carotid atherosclerosis was observ ed in the experimental groups.　The changes included endothelial regeneration, the proliferation of smooth muscle cells and monocytes, significant intimal thi ckening and secondary vascularization in intimal, the formation of connective t issue matrix comprising elastic and collagen, the accumulation of lipid and cho lesterol in the associated cells and in the surrounding matrix.　The neointimal thickening was significant at 2 week and 4 week in the experimental groups and t he I/M ratio reached 0.47±0.07 and 0.94±0.07.　Conclusions　The typical carotid atherosclerosis lesion can induced by cholesterol-diet pl u s air-drying in rabbit.　The pathological changes and its mechanisms were more suitable for the advanced research in experimental carotid atherosclerosis.