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

question 42

Multiple Choice

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

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Definitions:

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Stridor

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