The impact of selected vasoactive factors on vascular functions

The regulation of blood circulation is crucial for maintaining vascular homeostasis under physiological conditions, i.e. for precisely controlling the balance between vasodilators and vasoconstrictor action. Numerous studies show that both arteries and veins actively participate in the control process. This paper discusses the regulation of the secretion of selected vasoactive factors in endothelial cells. The mechanisms of action of those factors, the effect of other regulators on the function of vascular smooth muscle cells and the impact of physiological and pathological factors on the vasoreactivity are also examined. The synthesis and release of most vasodilators, including nitric oxide, carbon monoxide and prostacyclin, as well as vasoconstrictors – endothelin and thromboxane, takes place in endothelial cells. Prostaglandins F2α or E2 produced both in endothelial and other cells of bodily organs also influence blood vessel function. Steroid ovarian hormones, estradiol, progesterone and testosterone, affect vascular function indirectly by modulating endothelial secretory function. Blood vessel function largely depends on the activity of endothelial cells which release various vasoactive factors in response to stimulation. The resulting mutual interactions adjust vascular function to current needs. Endothelial dysfunction disrupts the activity of various organs, and it may contribute to cardiovascular diseases such as hypertension, atherogenesis or thrombotic lesions.