长期高脂饲料喂养对大鼠主动脉结构的影响

目的观察长期高脂饲料喂养对大鼠主动脉结构的影响。方法SD大鼠14只,分为对照组和实验组。实验组给予高脂饲料12wk后,取主动脉常规制备标本,用光镜、透射电镜和扫描电镜观察。结果实验组主动脉内膜增厚,内皮细胞损伤脱落,有单核细胞黏附;弹力膜断裂,平滑肌细胞增生。透射电镜下内皮细胞的胞膜破溃,呈虫蚀样改变。内皮细胞的线粒体肿胀、空泡变,嵴溶解、断裂、消失;内质网扩张。内皮细胞间隙增大,细胞连接失去正常形态。并可见黏附于内皮表面的单核细胞伸出伪足潜入内皮间隙、内皮下层。有的基底膜随内皮细胞完全脱落。平滑肌细胞粗面内质网和核糖体增多。扫描电镜下内皮细胞肿胀,细胞表面呈大小不等的虫蚀状或火山口状,细胞间出现深大的缝隙。结论长期高脂饲料喂养大鼠可引起主动脉的内皮和弹力膜损伤,单核细胞黏附并侵入内皮和内皮下层,内皮下层和平滑肌增生。

The influences on the structure of rats''''aorta with long-term high fat forages diet

Aim To investigate the influences on the aortal structure of rats with long-term high fat forages diet.Methods 14 SD rats were divided into two groups:the control group and the test group. The test rats were fed with high fat forages.12 weeks later, the aortas of the rats were observed with a light microscope, transmission electron microscope(TEM) and scanning electron microscope (SEM).Results In the test group, the aortic tunica intima thickening, endotheliocyte injury and monocyte adhesion were found with a light microscope; the elastic lamina being broken and the smooth muscle cells proliferated. Under TEM, the endothelial cell membrane of the aorta in the test rats was destroyed and appeared to be worm-eclipsed shape.Mitochondria exhibited swelling,vacuole degeneration and its cristae was dissolved, broken or some disappeared.Rough endoplasmic reticula (RER) expanded. The endothelial cell spaces were enlarged and the cell junctions deformed. Monocytes adhering to the endothelial cell stretched out pseudopodia and intruded into the endothelial crevice and the subendothelial layer. Some basement membranes completely sloughed following with endothelial cell. ERE and ribosomes increased in smooth muscle cells. SEM observation showed that the endothelial cells became swelling and the surface of endothelial cell was worm-eclipsed or crater shape. There were deeper crevices between endothelial cells.Conclusions Long-term high fat forages diet can induce injury of the endothelium and elastic lamina, adhesion of the monocytes and its intrusion into endothelial layer and subendothelial layer, proliferation of the subendothelial layer and smooth muscle in the aorta of rats.