[Formation and accumulation of myelin bodies and other membrane structures in the arterial wall in man in atherosclerosis].

Unaltered areas and fibrolipid plaques of various human arteries were examined electronmicroscopically. Myelin bodies were found to be produced by smooth-muscle cells of the intima and media of unaltered parts of the arterial wall. The formation of myelin bodies by smooth-muscle cells significantly increases in the fibrolipid plaques. Myelin bodies are frequently located in the cytoplasm matrix of altered smooth-muscle cells, in the areas of myofilament lysis. They are also found within mytochondria and in the cystern lumina of the granular cytoplasmatic reticulum. The accumulation of membranous structures in the fibrolipid plaques results from myelin-body production by smooth-muscle cells and vacuoles and vesicules of a varying size.