Search results
Results from the WOW.Com Content Network
Vasodilation occurs as part of the process of inflammation, which is caused by several factors including presence of a pathogen, injury to tissues or blood vessels, and immune complexes. [7] In severe cases, inflammation can lead to sepsis or distributive shock. [11] Vasodilation is also a major component of anaphylaxis. [12]
When environmental changes occur (e.g. exercise, immersion in water), neuronal and hormonal signals, including binding of norepinephrine and epinephrine to the α1 receptor on vascular smooth muscles, cause either vasoconstriction or vasodilation. Because resistance is inversely proportional to the fourth power of vessel radius, changes to ...
Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation , the widening of blood vessels.
For premium support please call: 800-290-4726 more ways to reach us
Vasodilation and vasoconstriction are complex phenomena; they are functions not merely of the fluid mechanics of pressure and tissue elasticity but also of active homeostatic regulation with hormones and cell signaling, in which the body produces endogenous vasodilators and vasoconstrictors to modify its vessels' compliance.
Agonists of alpha-2 receptors in the vascular smooth muscle lead to vasoconstriction. However, in clinical practice drugs applied intravenously that are agonists of alpha-2 receptors such as clonidine lead to powerful vasodilation, which causes a decrease in blood pressure by presynaptic activation of the receptors in the sympathetic ganglia ...
Both of these factors affect pH and, in turn, the balance between vasodilation versus vasoconstriction in the brain. [3] [4] So, the blood vessels found specifically in the brain respond changes in dissolved carbon dioxide levels. Coronary (heart) circulation is controlled at the local level primarily by metabolic control mechanism. More ...
When the blood vessels suddenly relax, it results in vasodilation. In vasodilatory shock, the blood vessels are too relaxed leading to extreme vasodilation and blood pressure drops and blood flow becomes very low. Without enough blood pressure, blood and oxygen will not be pushed to reach the body's organs.