A drug produces bradycardia that is blocked by atropine, vasodilation that persists after atropine, and stimulation of nicotinic ganglionic receptors. Which receptor profile matches this drug?

• A Selective muscarinic M2 agonist
• B Selective nicotinic NMJ agonist
• C Indirect cholinomimetic acting via acetylcholinesterase inhibition
• D Non-selective cholinomimetic acting on muscarinic and nicotinic receptors ✓

Explanation

Carbachol (and to some extent bethanechol) acts on both muscarinic and nicotinic receptors. Bradycardia is a muscarinic (M2) effect blocked by atropine; vasodilation in some vascular beds involves endothelial muscarinic receptors, while ganglionic stimulation is a nicotinic effect. An AChE inhibitor would also fit, but the question specifies direct receptor stimulation rather than inhibition of metabolism.

Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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