Which one is true about serotonin?: (A) Sleep suppressant, (B) Increase appitite, (C) Vasoconstriction, (D) Bronchodialtion
Answer is C. Serotonin is a powerful vasoconstrictor, produces hyperpnea, increases tone of smooth muscle of intestine, bronchioles.(Ref: Textbook of physiology N Geetha 2nd edition page no.446)