acetýlkolín

Acetylcholine is a neurotransmitter, a chemical messenger that transmits signals between nerve cells and also between nerve cells and muscles or glands. It is found throughout the body, playing crucial roles in both the central and peripheral nervous systems. In the peripheral nervous system, acetylcholine is essential for muscle contraction, as it binds to receptors on muscle fibers, triggering them to shorten. It also influences heart rate, digestion, and other autonomic functions.

Within the central nervous system, acetylcholine is involved in a variety of cognitive processes, including learning, memory, attention, and arousal. Degeneration of acetylcholine-producing neurons is a hallmark of Alzheimer's disease, contributing to the memory and cognitive deficits associated with this condition. Furthermore, acetylcholine acts as a mediator in the parasympathetic nervous system, often referred to as the "rest and digest" system, counteracting the effects of the sympathetic nervous system. Its synthesis occurs in the nerve terminal from choline and acetyl-CoA, and its breakdown is rapidly accomplished by the enzyme acetylcholinesterase, allowing for precise and timely signal transmission.