Beta-blockers are a class of drugs that target beta-adrenergic receptors,blocking the action of epinephrine and norepinephrine.These drugs are used to treat heart conditions,hypertension,glaucoma,and migraine headaches and are also used off-label to alleviate stage fright in performers.Since the beta-adrenergic receptor is a GPCR,what intracellular event is prevented by the use of a beta-blocker?
A)a protein kinase cascade,initiated by the receptor's intracellular kinase domain
B)release of an activated G protein subunit bound to GTP
C)transport of the receptor-hormone complex into the cell and the nucleus,where it would regulate transcription
D)a protein phosphatase cascade,initiated by the receptor's intracellular phosphatase domain

Question

Quizplus · Accepted Answer

Beta-blockers prevent the release of an activated G protein subunit bound to GTP, as beta-adrenergic receptors are G protein-coupled receptors (GPCRs) that typically activate this pathway upon binding of their ligands.

Beta-Blockers Are a Class of Drugs That Target Beta-Adrenergic Receptors,blocking