Which of the following is most apt to cause a (+) inotropic effect?
A)Activation of the alpha1-adrenergic receptors by ACh
B)Activation of the muscarinic receptors by NE
C)Blockade of alpha1-adrenergic receptors
D)Use of a Beta₁-adrenergic agonist

Question

Quizplus · Accepted Answer

Beta₁-adrenergic agonists are known to increase the force and rate of myocardial contraction, resulting in a (+) inotropic effect. ACh does not activate alpha1-adrenergic receptors (it activates nicotinic receptors), and NE does not activate muscarinic receptors (it activates adrenergic receptors). Additionally, blockade of alpha1-adrenergic receptors would result in a (-) inotropic effect.

Which of the Following Is Most Apt to Cause a (+)