Diffuse intimal thickening in chronic obliterating disease of arteries of the lower extremities in humans.
The concept of atherosclerosis is essentially applicable to the arteries of the elastic type. Lesions in the arteries of the muscular type have a different character. They show an association of fibrosis of the media with a diffuse intimal thickening and the presence of stratified fibro-hyaline plaques, representing organized parietal thrombi. Deposition of lipids is weak or moderate and apparently a secondary event. Intimal thickening of peripheral arteries exceeds largely the limits of the thrombotic zone. It is covered by normal endothelium and populated by myocytes with a few fibroblasts. The intercellular substance shows all stages of formation of elastic structures, a process which is probably related to the activity of myocytes. It leads to the formation of one or several fairly distinct elastic membranes. Concomitantly the lamina elastica interna undergoes considerable degradation. We are, thus, confronted with a lesion of considerable age which, nevertheless, remains active and shows continuing structural changes. The origin of cells in intimal thickening and its significance in terms of general pathology are discussed with respect to the experimental results.
D000328:Adult; D000368:Aged; D001157:Arterial Occlusive Diseases / Q000473:pathology*; D001161:Arteriosclerosis / Q000473:pathology; D001162:Arteriosclerosis Obliterans / Q000473:pathology; D005260:Female; D005263:Femoral Artery; D006801:Humans; D007083:Iliac Artery; D007866:Leg / Q000098:blood supply; D008297:Male; D008875:Middle Aged; D011150:Popliteal Artery; D013927:Thrombosis / Q000473:pathology*