[New findings on the structure of normal blood vessels according to rastral electron microscopy data].

Under rastral electron microscopic study were the internal surface of the aorta of 48 humans from 2 weeks to 75 years of age, the large cutaneous vein of the shank in 14 humans from 12 to 58 years of age, the femoral artery and vein in 8 mongrel dogs. It was established that the internal surface of blood vessels was not a smooth-walled cylinder but a structure with a complicated relief. The microrelief of the internal surface is formed of subendothelially disposed collagenous-elastic formations and configuration of the endothelial cells cytoplasm. It consists of folds of the first and second order, which make the internal square surface of the blood vessels 3-4 times larger. There are some peculiar features in the structure of the internal surface of arteries and veins which, to the author's opinion, might be due to differences in the structure of collagenous-elastic constructions of the wall of these vessels. Certain developmental changes of the internal surface of the aorta are described. The authors believe that the special microrelief of the internal surface of blood vessels is of particular significance for hemodynamics, the exchange of substances between the blood and vascular wall and for the thrombus formation. These new findings should be presented in manuals and textbooks on anatomy, histology and embryology.