Which neurotransmitter is primarily affected by cholinergic agonists?

Cholinergic agonists primarily affect acetylcholine, which is the main neurotransmitter in the cholinergic system. These agents enhance or mimic the action of acetylcholine at cholinergic receptors, which are found throughout the nervous system, including both the central and peripheral nervous systems. The stimulation of these receptors leads to various physiological responses, such as muscle contraction, increased glandular secretions, and modulation of different autonomic functions.

Acetylcholine plays a critical role in transmitting signals in both the somatic and autonomic nervous systems, impacting processes like muscle movement, heart rate regulation, and cognitive function. The therapeutic uses of cholinergic agonists often target conditions related to inadequate acetylcholine signaling, such as myasthenia gravis or certain types of dementia.

The other neurotransmitters listed—dopamine, norepinephrine, and serotonin—are not directly targeted by cholinergic agents. Instead, they belong to different neurotransmitter systems and have distinct functions and pathways in the body.