Distribution of type IV collagen, laminin, nidogen and fibronectin in the haemodynamically stressed vascular wall

Abstract

Changes in the extracellular matrix of haemodynamically stressed blood vessel walls were studied by immunofluorescence histochemistry in venous-pouch aneurysms fashioned on the site of the common carotid artery of nine sheep. Tissues from the thickened walls of the experimental aneurysms were examined from 11 to 98 months post-operatively for changes in the distribution of the basement membrane components type IV coliagen, laminin, nidogen and fibronectin. In the younger aneurysms, there was an increase of the basement membrane components in the thickened area. Very little basement membrane was detected in older aneurysms. Diffuse staining for fibronectin was noted in aneurysms of al1 ages. Thick deposits of basement membrane material were observed in calcified tissues. The changes in the matrix próteins were similar to alterations occurring dunng the development of atherosclerosis in human vascular tissue.