Search results
Results from the WOW.Com Content Network
Acetylcholine processing in a synapse. After release acetylcholine is broken down by the enzyme acetylcholinesterase. Like many other biologically active substances, acetylcholine exerts its effects by binding to and activating receptors located on the surface of cells. There are two main classes of acetylcholine receptor, nicotinic and muscarinic.
Although all acetylcholine receptors, by definition, respond to acetylcholine, they respond to other molecules as well. Nicotinic acetylcholine receptors (nAChR, also known as "ionotropic" acetylcholine receptors) are particularly responsive to nicotine. The nicotine ACh receptor is also a Na +, K + and Ca 2+ ion channel.
Antinicotinic agents (also known as ganglionic blockers, neuromuscular blockers), including tubocurarine and hexamethonium, block acetylcholine action at nicotinic acetylcholine receptors. Their effects are based on the expression of corresponding receptors in different parts of the body.
The protein encoded by this gene synthesizes the neurotransmitter acetylcholine. Acetylcholine acts at two classes of receptors in the central nervous system – muscarinic and nicotinic – which are each implicated in different physiological responses. The role of acetylcholine at the nicotinic receptor is still under investigation.
The enzyme acetylcholine esterase breaks down the neurotransmitter acetylcholine, which is released at nerve and muscle junctions, in order to allow the muscle or organ to relax. The result of acetylcholine esterase inhibition is that acetylcholine builds up and continues to act so that any nerve impulses are continually transmitted and muscle ...
Similarly, acetylcholine released from parasympathetic neurons may interact with M 2 and M 4 receptors to inhibit further release of acetylcholine. An atypical example is given by the β-adrenergic autoreceptor in the sympathetic peripheral nervous system, which acts to increase transmitter release. [1]
In vertebrates, motor neurons release acetylcholine (ACh), a small molecule neurotransmitter, which diffuses across the synaptic cleft and binds to nicotinic acetylcholine receptors (nAChRs) on the cell membrane of the muscle fiber, also known as the sarcolemma. nAChRs are ionotropic receptors, meaning they serve as ligand-gated ion channels ...
The released ATP acts on purinergic receptors on endothelial cells, triggering the synthesis and release of several vasodilators, like nitric oxide (NO) and prostacyclin (PGI 2). [ 40 ] [ 41 ] The current model of leukocyte adhesion cascade includes many steps mentioned in Table 1. [ 42 ]