Studies on nicotinic acetylcholine receptors in mammalian brain. Preliminary characterization of membrane-bound alpha-bungarotoxin receptors in rat cerebral cortex. J Biol Chem 1976 Oct 25;251(20):6335-9
Date
10/25/1976Pubmed ID
977573Scopus ID
2-s2.0-0017183185 (requires institutional sign-in at Scopus site) 52 CitationsAbstract
Binding of alpha-bungarotoxin, labeled with 125I, has been studied in crude membrane preparations of rat cerebral cortex. Membrane-bound receptors appear to consist of at least two saturable subsets: one accounts for the binding of about 50 fmol of toxin/mg of protein, the other binds 120 fmol/mg. For the high affinity sites the dissociation constant for interaction of toxin and receptor extrapolated to zero protein concentration is 9.2 X 10(-10) M. Competition with a variety of agonists and antagonists indicates that toxin binding exhibits the pattern expected for nicotinic acetylcholine receptors. Toxin binding is inhibited by low concentrations of Ca2+ ions (50% inhibition at 3 mM) while higher concentrations are required for Mg2+, Na+, K+, and Li+ (50% inhibition at 0.5 M).
Author List
McQuarrie C, Salvaterra PM, De Blas A, Routes J, Mahler HRMESH terms used to index this publication - Major topics in bold
AcetylcholineAnimals
Binding, Competitive
Bungarotoxins
Cations, Divalent
Cations, Monovalent
Cell Membrane
Cerebral Cortex
Kinetics
Ligands
Male
Rats
Receptors, Cholinergic
Receptors, Nicotinic