動・静脈血栓形成過程に関する基礎的研究 走査および透過電子顕微鏡による観察

Abstract

The process of thrombus formation at arterial and venous endothelial surfaces was examined by scanning electron microscope (SEM) and transmission electron microscope (TEM) in a photochemical occlusion model.The rats were divided into the following 4 groups after the injection of rose bengal:1) control group (n=5)without illumination; 2) group A (n=10) irradiated for 1 min; 3) group B (n=10) for 5 min; 4) group C (n=14) for lO min at cervical artery and vein. As a result, SEM findings showed adhesion of blood platelets and endothelial damage in neither artery nor vein in control and A groups. Plasma membrane damage of endothelial cells (i.e. plasmalemmal pits, the crater-like structure associated with tear between endothelial cells, and decreased number of microvilli) was recognized in arterial wall, but these changes were not observed in vein in group B. Adhesion of blood platelets in addition to endothelial cell membrane obstacle in artery was remarkable by SEM examination and tear between arterial endothelial cells was found by TEM examination in group C. The degree of adhesion of platelets was clearly remarkable in artery compared with vein. In conclusion, endothelial cell membrane injury, tear between endothelial cells and endothelial detachment occur before adhesion of blood platelets and thrombus formation in a blood vessel occlusion model by photochemical reaction. These changes occur significantly earlier in artery than in vein.