[Erythrocyte concentration in vessels of the microcirculatory bed of the mesentery of the white rat (according to the results of in vivo microcinematography)].

The red cells velocity and hematocrit value were studied with high-speed microfilming in microvessels of albino rat mesentery. Decrease of the red cells velocity and increase in the number of microvascular branching were followed by a decrease in the hematocrit value: 20% in the precapillary arterioles and 16% in capillaries. The concentration of erythrocytes increased to 26% in venules. The magistral communication between arterioles and venules has a specific place among microvessels. These channels are relatively wider, the red cells velocity is high (0.9 mm/sec) as well as the hematocrit value (23%). Variation of hematocrit value in capillaries is not solely the function of their volume but also the function of their position in capillary net.