Agonists block currents through acetylcholine receptor channels.

S M Sine; J H Steinbach

doi:10.1016/s0006-3495(84)84022-9

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Agonists block currents through acetylcholine receptor channels.

S M Sine·J H Steinbach

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Abstract

We have examined the effects of high concentrations of cholinergic agonists on currents through single acetylcholine receptor (AChR) channels on clonal BC3H1 cells. We find that raised concentrations of acetylcholine (ACh; above 300 microM) or carbamylcholine (Carb; above 1,000 microM) produce a voltage- and concentration-dependent reduction in the mean single-channel current. Raised concentrations of suberyldicholine (Sub; above 3 microM) produce a voltage- and concentration-dependent increase in the number of brief duration low-conductance interruptions of open-channel currents. These observations can be quantitatively described by a model in which agonist molecules enter and transiently occlude the ion-channel of the AChR.

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Acetylcholine Animals Carbachol Cell Line Choline Clone Cells Electric Conductivity Membrane Potentials Mice Receptors, Cholinergic Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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S M Sine, J H Steinbach. 1984. Agonists block currents through acetylcholine receptor channels.. https://doi.org/10.1016/s0006-3495(84)84022-9

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