Single Microelectrode Analysis of Electrically Coupled Networks

The mathematical analysis of a simple, two-compartment model of an electrically coupled system of cells shows that each of the electrical parameters of the system can be estimated from intracellularly recorded potentials following the injection of steps of current. This model provides a useful basis to monitor changes in coupling and membrane properties in electrical syncytia. The model has been shown to accurately describe coupling 1) between identified pairs of electrically coupled neurons and 2) in an electrical syncytium of secretory cells in the freshwater snail Helisoma trivolvis. Using standard electrophysiological techniques, each of the electrical parameters of the coupled system can be determined from dynamic responses using a single microelectrode, suggesting a variety of applications in numerous tissues containing electrotonic junctions.