Cardiac hyperaemia/vasodilation is due to which mediator?
Histamine and adenosine are vasodilators seen in cardiac muscles.Parasympathetic stimulation releases Ach at their endings which causes vasodilation. The effect is more in glands and GIT.Adrenaline acts alpha and beta receptors. It causes vasoconstriction alpha receptors in the blood vessels of the skin and mucous membrane whereas on skeletal blood vessels beta receptor stimulation causes vasodilation. cardiac acceleration by adrenaline is beta-receptor stimulation.Except in kidney dopamine produces vasoconstriction. Ref: Textbook of medical physiology by N Geetha, 2nd edition, page no. 181,182,351
Ach
Adrenaline
Dopamine
Adenosine
Cardiovascular system