Single-shot channel activation accounts for duration of inhibitory postsynaptic potentials in a central neuron.
In the goldfish Mauthner cell, inhibitory postsynaptic currents evoked by intracellular stimulation of presynaptic neurons decay exponentially, with a mean time constant of 6.65 milliseconds. Analysis of membrane conductance fluctuations induced by iontophoresis of glycine and gamma-aminobutyric acid indicates a mean inhibitory channel lifetime of 7.15 milliseconds. The results thus suggest that the relaxation kinetics of activated inhibitory channels are rate-limiting during decay of the inhibitory postsynaptic current.
D000818:Animals; D002531:Cerebellum / Q000166:cytology; D002712:Chlorides / Q000502:physiology; D004553:Electric Conductivity; D005998:Glycine / Q000494:pharmacology; D006054:Goldfish; D007473:Ion Channels / Q000502:physiology*; D008564:Membrane Potentials / Q000187:drug effects*; D009433:Neural Inhibition; D009474:Neurons / Q000502:physiology*; D011149:Pons / Q000166:cytology; D013997:Time Factors; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology
D002712:Chlorides; D007473:Ion Channels; D005680:gamma-Aminobutyric Acid; D005998:Glycine