What is the primary mechanism of action of nicotine?
ExplanationD. Nicotine is an agonist at nicotinic acetylcholine receptors. Nicotine leads to increased levels of several neurotransmitters, especially dopamine, in the reward circuits of the brain. This leads to euphoria, relaxation, and addiction. Nicotine in tobacco stimulates several areas in the reward circuit and its connections, such as the noradrenergic neurons of the locus coeruleus. Several other areas in the brain that secrete acetylcholine, such as the hippocampus and cortex, also appear to be affected by nicotine, and this may explain the increased attentiveness that smokers often describe after nicotine ingestion.
