Structure And Function Of Acetylcholine

ACETYLCHOLINENerve cellAcetylcholine is a neurotransmitter at many synapses and nerve-muscle junctions.The presynaptic membrane of the cholinergic synapse (one that uses acetylcholine as a neurotransmitter) is separated from the postsynaptic membrane by a gap (500 A) called a synaptic cleft.The end of the presynaptic axon is filled with synaptic vesicles containing acetylcholine.The arrival of a nerve impulse leads to the release of acetylcholine into the cleft.The acetylcholine then diffuses to the postsynaptic membrane where they combine with specific receptors.This produces depolarization of the postsynaptic membraneThis is propagated along the electrically excitable membrane of the second nerve cell.Acetylcholine is then hydrolyzed by acetylcholinesterase enzyme.Polarization of the postsynaptic membrane is restored.Acetylcholine is released in packetsAcetylcholine also opens cation gates in the postsynaptic membrane.Acetylcholinesterasese inhibitors are used as drugs and poisons- neostigmine and physostigmineAcetylcholine Precursors:Choline and acetyl-CoASynthesizing enzymes: Choline acetyltransferaseMetabolizing enzymes: AcetylcholinesteraseMetabolites: Choline and acetateThe chemical compound acetylcholine (often abbreviated ACh) is a neurotransmitter in both the peripheral nervous system (PNS) and central nervous system (CNS) in many organisms including humans. Acetylcholine is one of many neurotransmitters in the autonomic nervous