19.1 Regulation of regional hemodynamics
19.2 Blood supply to the brain
19.3 Coronary circulation
19.4 Cutaneous circulation
19.5 Circulation in skeletal muscles
19.6 Celiac circulation
19.7 Pulmonary circulation
19.8 Renal circulation
Control questions Situational tasks
19.1. Regulation of regional hemodynamics
Regional hemodynamics is blood circulation in the vascular bed of individual organs connected in parallel to the aorta and the vena cava. It is characterized by various hemodynamic phenomena. The most important manifestation of this type of blood circulation is transport of blood in the microvessels of organs, called mi-crocirculation.
Functional components of an organ (A.M. Chernukh, 1979) involve a complex microsystem, including cellular and non-cellular components specific to each organ, which are concentrated around the microvessels and integrated with them into an integrated system by regulatory mechanisms.
Microcirculation is transport of blood in microves-sels, transport of intercellular fluid and lymph in the initial part of the lymphatic system.
Microcirculation vessels
Arterioles and precapillaries create hydrodynamic resistance to circulation, determining the ways and conditions of blood delivery to the capillaries, distribute the circulation depending on the number of functioning capillaries.
Capillaries and postcapillaries perform an exchange (nutritional and excretory) function. Postcapillaries also determine the paths and conditions for the outflow of blood from the microvasculature.
Venules mainly determine the capacitive function and, due to the presence of valves, determine the direction of circulation.
Arteriovenous anastomoses provide the possibility of bypassing the circulation by bypassing the capillary bed. Their shunting function allows the body to regulate capillary (nutrient) circulation in various functioning organs at any given moment.