[Comparative study of the proliferative activity of blood vessel cells of various calibers].

Proliferative activity of the main tissue components of aorta, inferior vena cava and small vessels of paravasal tissues has been studied in 7 white adult rats after repeated injections of 3H-thymidine (12 injections of 0.8 microCi/g with the interval of 8 h). The greatest number of labelled endotheliocytes is revealed in capillaries, small and medium veins (29.4 +/- 6.2%). Proliferative activity of smooth muscle cells in arterioles was by 2 times greater than in other vessels. There was no difference between the number of labelled fibroblasts in the media of all types of studied vessels.