Cardiac activity is increased when norepinephrine binds on which of these receptors on cardiac muscle
A)cholinergic
B)nicotinic
C)alpha
D)beta-1

Question

Quizplus · Accepted Answer

Norepinephrine is a sympathetic neurotransmitter that increases heart rate and contractility through beta-1 adrenergic receptors located in the cardiac muscle. Choice A (cholinergic) and B (nicotinic) are receptors that bind to acetylcholine, a parasympathetic neurotransmitter that slows down heart rate and contractility. Alpha receptors (choice C) are present in the smooth muscles and help in vasoconstriction, but not in the cardiac muscle.

Cardiac Activity Is Increased When Norepinephrine Binds on Which of These