Nicotine is an agonist at which receptors?

Nicotine is an agonist at which receptors?

• A. GABA receptors
• B. Muscarinic acetylcholine receptors
• C. Dopamine receptors
• D. Nicotinic acetylcholine receptors

Answer: (D)

Nicotine acts as an agonist on nicotinic acetylcholine receptors, which are ligand-gated ion channels located in the brain, autonomic ganglia, and at the neuromuscular junction. When nicotine binds, these receptors open and allow positively charged ions to flow in, depolarizing the cell and increasing neuronal firing. This direct activation of nicotinic receptors explains nicotine’s quick and widespread stimulatory effects and its powerful reinforcing properties, especially since activating nAChRs on dopaminergic neurons boosts dopamine release in reward pathways. The other receptor types aren’t directly activated by nicotine. GABA receptors are inhibitory chloride channels; muscarinic acetylcholine receptors are GPCRs activated by acetylcholine rather than nicotine; dopamine receptors are GPCRs that respond to dopamine, not nicotine (though nicotine can influence dopamine levels indirectly).

Nicotine acts as an agonist on nicotinic acetylcholine receptors, which are ligand-gated ion channels located in the brain, autonomic ganglia, and at the neuromuscular junction. When nicotine binds, these receptors open and allow positively charged ions to flow in, depolarizing the cell and increasing neuronal firing. This direct activation of nicotinic receptors explains nicotine’s quick and widespread stimulatory effects and its powerful reinforcing properties, especially since activating nAChRs on dopaminergic neurons boosts dopamine release in reward pathways.

The other receptor types aren’t directly activated by nicotine. GABA receptors are inhibitory chloride channels; muscarinic acetylcholine receptors are GPCRs activated by acetylcholine rather than nicotine; dopamine receptors are GPCRs that respond to dopamine, not nicotine (though nicotine can influence dopamine levels indirectly).