A certain drug decreases heart rate by blocking a receptor on cardiac pacemaker cells. This drug probably binds to ________ receptors.
A) nicotinic cholinergic
B) muscarinic cholinergic
C) alpha-1 adrenergic
D) alpha-2 adrenergic
E) beta-1 adrenergic

Question

Quizplus · Accepted Answer

Beta-1 adrenergic receptors are primarily found in the heart, and their blockade leads to a decrease in heart rate. This is a common mechanism of action for beta-blocker medications used in treating high blood pressure and heart conditions.

A Certain Drug Decreases Heart Rate by Blocking a Receptor