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decrease in the caliber of blood vessels. adj., adj vasoconstric´tive.
Narrowing of the blood vessels.
vasoconstriction/vaso·con·stric·tion/ (-kon-strik´shun) decrease in the caliber of blood vessels.vasoconstric´tive
Constriction of a blood vessel, as by a nerve or drug.
Etymology: L, vas + constrigere, to tighten
a decrease in the diameter of a blood vessel. It plays an important role in the control of blood pressure and the distribution of blood throughout the body. Vasoconstriction is triggered by stimulation of the vasomotor constriction center in the medulla. Impulses from this center travel along sympathetic nerve fibers and cause contraction of the smooth muscle layers of arteries, arterioles, and, to a lesser extent, venules, and veins, bringing about constriction of these vessels. Vasoconstriction is also induced by vasomotor pressure reflexes, chemical reflexes, the medullary ischemic reflex, and impulses from the cerebral cortex and the hypothalamus. Compare vasodilation. vasoconstrictive, adj.
Reduction in the caliber of a blood vessel due to contraction of smooth muscle fibers in the tunica media leading to decreased blood flow to a part.
vasoconstrictionActive narrowing of small arteries as a result of contraction of the circular smooth muscle fibres in their walls. This severely reduces the flow of blood through them. Compare VASODILATATION.
vasoconstrictiona narrowing of the blood vessels, often in response to cold, which occurs through a contraction of INVOLUNTARY muscles in the walls of the vessels brought about by a stimulus from the sympathetic nervous system (see AUTONOMIC NERVOUS SYSTEM).
Constriction of a blood vessel.
Mentioned in: Induction of Labor
n state of constriction or narrowing of a blood vessel.
Narrowing of blood vessels.
decrease in the caliber of blood vessels; may be general or local, e.g. pulmonary, peripheral.