The dissociation of acetylcholine from open nicotinic receptor channels
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چکیده
منابع مشابه
The dissociation of acetylcholine from open nicotinic receptor channels.
Ligand-gated ion channels bind agonists with higher affinity in the open than in the closed state. The kinetic basis of this increased affinity has remained unknown, because even though the rate constants of agonist association to and dissociation from closed receptors can be estimated with reasonable certainty, the kinetics of the binding steps in open receptors have proven to be elusive. To b...
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We have studied the binding of alpha-bungarotoxin to a particulate fraction of goldfish brain enriched in synaptosomes. The binding is specific and saturable and exhibits the pharmacological properties of a nicotinic cholinergic receptor. Equilibrium binding measurements yield a single dissociation constant (KD) of 0.92 nM. Kinetic analysis revealed one association rate constant and two dissoci...
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The nicotinic acetylcholine receptor (nAChR) is a cation-selective channel central to both neuronal and muscular processes and is considered the prototype for ligand-gated ion channels, motivating a structural determination effort that spanned several decades [Unwin N (2005) Refined structure of the nicotinic acetylcholine receptor at 4 A resolution. J Mol Biol 346:967-989]. Purified nAChR must...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 2001
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.251402498