Single-Channel Currents and Postsynaptic Drug Actions
In single-channel recordings, the gating transitions of individual ionic channels appear as a stochastic process. The description of the random transitions of a channel between its discrete conductance states complements the kinetic picture of the gating process derived from macroscopic experiments such as voltage clamp, noise analysis, or gating current. The goals of kinetic measurements are to derive unique reaction schemes for modeling macroscopic excitation phenomena and perhaps to obtain some insights about the molecular motions involved in the conformation changes attendant to gating. In this chapter, I show how the rates of a kinetic process are inferred from single-channel data and how such analysis can be applied to the study of drug action on postsynaptic channels.
KeywordsClosed State Kinetic Scheme Postsynaptic Response Acetylcholine Receptor Channel Endogenous Transmitter
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