n. [ L. acetum vinegar + Gr. &unr_; substance. See -yl. ] (Chem.) A complex, hypothetical radical, composed of two parts of carbon to three of hydrogen and one of oxygen. Its hydroxide is acetic acid. [ 1913 Webster ]
n. 1. a neurotransmitter released by the transmitting dendron at autononmous synapses and at neuromuscular junctions. It is a quaternary amine with an obligatory negative counterion. The nominal formula for the hydroxide form is C7H17NO3. Structural formula (CH3)3N(+)CH2CH2.O.CO.CH3.OH(-). Acetylcholine is the first recognized and best-studied of the neurotransmitters. At receptors it is recycled into choline by the action of acetylcholinesterase. Acetylcholinesterase inhibitors therefore function as nerve poisons. For biochemical studies it is prepared typically in the chloride or bromide forms. [ WordNet 1.5 +PJC ]
n. 1. an enzyme which exists in nerve cells and hydrolyses acetylcholine into choline and acetic acid. It is essential for neurotransmission at autonomous synapses and neuromuscular junctions, and its inhibition by acetylcholinesterase inhibitors can paralyze or kill an animal. Syn. -- ACE [ PJC ]
n. (Chem.) A gaseous compound of carbon and hydrogen, in the proportion of two atoms of the former to two of the latter. It is a colorless gas, with a peculiar, unpleasant odor, and is produced for use as an illuminating gas in a number of ways, but chiefly by the action of water on calcium carbide. Its light is very brilliant. Watts. [ 1913 Webster ]
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