Elimination of Errors in Evaluation of Gap Junction Single Channel Conductance

Abstract

Errors in evaluation of conductance of single gap junction channels could appear due to the artifact steps in inter-cellular current signal registered using Double Whole Cell Voltage Clamp method at very high amplification (current in ran-ge of picoamperes must be registered). The idea of method to eliminate the error measures of conductance of single gap junction channels is based on already known electrical properties of the channels. Conductance of single gap junction channel is either voltage independent or could vary in regard to transjunctional voltage switching between substates of fixed conduc-tance. A surface diagram constructed from histograms of conductance at various voltages reveals conductance of channel substates as prolonged surface peaks laying in parallel to the voltage axis. Error conductance measures made on artifact current steps in registered intercellular current signal show voltage dependency of it. Modeling showed them forming a curve or irregular form surface peaks on surface histogram.