Platelet adhesion to subendothelial components in experimental aortic injury. Role of fine fibrils and basement membrane.

The intact intima of the rabbit abdominal aorta contained a well-defined, fairly continuous endothelial basement membrane and a network fo fine fibrils, which branched from both sides of the basement membrane. Partial ligation of the abdominal aorta of the rabbit resulted in endothelial desquamation, but left a layer of subendothelial fine fibrils and occasionally, segments of endothelial basement membrane. Platelets adhered to exposed fine fibrils including those extending from basement membrane fragments. Adhesion to occasionally exposed collagen fibres occurred but there was no direct adhesion to exposed internal elastic lamina or elastin fragments, for these elements were always covered by a thin layer of fine fibrils.