维生素D诱发大鼠动脉粥样硬化的实验研究

EXPERIMENTAL ATHEROSCLEROSIS IN RATS INDUCED BY VITAMIN D

Twenty four male Wistar rats were divided into 4 equal groups at random,with 3 groups for experiments and 1 for control.Atherosclerotic lesions of the aorta were induced in experimental groups by intraperitoneal injection of vitamin D with a single dose of 600 000 international units per kilogram body weight.The 3 experimental groups were sacrificed at intervals of 3,18 and 34 days respectively and the control group at 34 days,Specimens from thoracic and abdominal aorta were taken for observation. The results showed:Under light microscope there were slight proliferation of smooth muscle cells and edematous degeneration of endothelial cells and subendothelial tissue at the end of the 18th day.The elastic laminae ruptured and smooth muscle cells proliferated. Projected atherosclerotic plaques were seen on the luminal surface of the aortic wall between 18 and 34 days,Under electron microscope,projections of endothelial cells were observed on the luminal surface and there were vesicles of various sizes in the cytoplasm by the end of the 3rd day up to 18 days,projections of the endothelial cells were numerous and microvillous;After 18 days,nuclei of the endothelial cells became twisted and smooth muscle cells migrated from tunica media to intima through the ruptured elastica interna. Some smooth muscle cells had become foam cells,The structure of the control group remained intact.This study offers a simple,economic and quick method for induction of atherosclerosis in experimental animals.