Control of intercellular communication by voltage dependence of gap junctional conductance

摘要: The junctional conductance between coupled amphibian blastomeres exhibits a high degree of voltage dependence, as previously described in clamp studies (Spray, D.C., A.L. Harris, and M.V.L. Bennett (1981) J. Gen. Physiol. 77: 77–95; A.L., D.C. Spray, 95–117). present study examines the properties which this dependence confers on electrotonic coupling cells. effects applied pulses ramps current are studied experimentally modeled by calculation. During sufficiently large to one cell pair, cells uncouple then recouple after termination pulses. Ramps can give voltage-current (V-I) relations with region hysteresis within stably or uncoupled depending previous history. Intrinsically generated currents able cause bistability absence externally current. Calculations from parameters defined under fully account for these findings illustrate how nonjunctional conductances affect V-I bistability. Recordings several small group show that boundaries intercellular communication be altered current, finding also accounted conductance. “Appendix” quantitatively criteria required relevance signaling. plasticity offers an intriguing mechanism patterns could determined changed developing tissues.