vasomotion

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vasomotion

 [vas″o-mo´shun]
change in caliber of blood vessels.

va·so·mo·tion

(vā'sō-mō'shŭn, vas-ō-),
Change in caliber of a blood vessel.

vasomotion

A term referring to the cyclical variation of vascular tone (vasodilaton and vasoconstriction), which is under hormonal, neural and local control.

Vasomotion
Homonal control
• Aldosterone—promotes salt retention.
• Angiotensin II—vasoconstrictor, increases blood pressure.
• Antidiuretic hormone—promotes water retention.
• Atrial natriuretic peptide—Promotes salt excretion.
• Epinephrine—increases blood flow.
• Norepinephrine—increases blood flow.

Neural control
• Baroreflex—responds to increased pressure signals detected by the carotid sinus, sending the signal via the glossopharyngeal nerve to the vasomotor centre, resulting in a decrease in sympathetic tone and increased parasympathetic tone; the opposite occurs with hypotension—i.e., an increase in sympathetic tone and a decrease in parasympathetic tone.
• Chemoreflex—responds to changes in pH, CO2 and O2 by adjusting rates of respiration.
• Medullary ischaemic reflex—responds to sudden drops in blood supply to the brain by increasing the heart rate.

Local control
• Vasodilation in response to local ischaemia and accumulation of waste products.
• Angiogenesis in response to chronic ischaemia.

va·so·mo·tion

(vā'sō-mō'shŭn)
Change in caliber of a blood vessel.
Synonym(s): angiokinesis.

vasomotion

change in caliber of blood vessels.