Cholinergic is an adjective that pertains to, activates, or relates to acetylcholine, a neurotransmitter in the central and peripheral nervous systems. It refers to any nerve fiber or receptor that is directly affected or influenced by acetylcholine. Acetylcholine plays a crucial role in the transmission of nerve impulses within the parasympathetic division of the autonomic nervous system.
In a biological context, cholinergic can describe any substance, drug, or agent that mimics or enhances the effects of acetylcholine, or that activates cholinergic receptors. These agents work by either increasing the release of acetylcholine or by inhibiting its breakdown, thereby promoting the transmission of impulses across cholinergic synapses. Examples of cholinergic substances include acetylcholinesterase inhibitors, such as donepezil, used in the treatment of Alzheimer's disease.
Cholinergic neurotransmission is essential for various physiological processes, including the regulation of heart rate, digestion, glandular secretion, muscle contraction, and memory formation. A disruption of cholinergic function can lead to pathological conditions like Alzheimer's disease, myasthenia gravis, and certain psychiatric disorders.
Furthermore, the cholinergic system also refers to a network of neurons in the brain that uses acetylcholine as its primary neurotransmitter. This system, known as the cholinergic system, impacts higher cognitive functions, attention, alertness, and arousal.
