Agonists block currents through acetylcholine receptor channels

Biophys J. 1984 Aug;46(2):277-83. doi: 10.1016/S0006-3495(84)84022-9.


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.

Publication types

  • 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.

MeSH terms

  • Acetylcholine / pharmacology*
  • Animals
  • Carbachol / pharmacology*
  • Cell Line
  • Choline / analogs & derivatives*
  • Choline / pharmacology
  • Clone Cells
  • Electric Conductivity / drug effects
  • Membrane Potentials / drug effects
  • Mice
  • Receptors, Cholinergic / drug effects
  • Receptors, Cholinergic / physiology*


  • Receptors, Cholinergic
  • subecholine
  • Carbachol
  • Choline
  • Acetylcholine