VPT-0138
QUESTION
Which of the following is as selective antagonist of M3-mAChRs??
OPTIONS
(A) Methacholine
(B) Methoctramine
(C) Darifenacine
(D) All of the above
ANSWER
(C) Darifenacine
EXPLANATION
Darifenacin is relatively selective for M3 muscarinic receptors and is used for its effects on smooth muscle and bladder function. Methacholine is an agonist, methoctramine is M2 selective, and all of the above is incorrect.
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Veterinary Pharmacology and Toxicology · 167 Questions
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