Localizing the site of generation of uni-quantal endplate potentials using two intracellular microelectrodes.
By recording with a microelectrode at either end of the endplate, the site of generation of uni-quantal endplate potentials (EPP) can be estimated. One method assumes that the logarithm of the amplitude of the signal declines linearly with distance along the cable [4, 8]. The uncertainties in this method are discussed. We show that even on a muscle cable the logarithm of the time integral of the EPP declines linearly with distance, falling to 1/e at a distance equal to the length constant, lambda. We conclude that the integral approach provides a theoretically sound method for localizing the sites of uniquantal EPP generation with two microelectrodes.
D000818:Animals; D004594:Electrophysiology; D007425:Intracellular Membranes / Q000502:physiology; D008839:Microelectrodes; D008959:Models, Neurological; D009045:Motor Endplate / Q000502:physiology*; D009469:Neuromuscular Junction / Q000502:physiology*