Gap junction change in supporting cells of the organ of Corti with ryanodine and caffeine

It has been demonstrated that the gap junctions of the supporting cells of the organ of Corti are controlled by H+ and Ca2+. Inside these cells there is a tubular structure. It is supposed that this network is endoplasmic ret iculum. Calcium release from inside the cells, and the effect of calcium on the gap junctions of these cells, were investigated under whole cell clamp ing application of ryanodine and caffeine. Membrane capacitance and membran e resistance were calculated with corrections for changes in whole cell par ameters. Ryanodine-treated cells (1 mu M-10 mM), caffeine-treated cells (5 mM-500 nM) and A23187-treated cells were uncoupled at their gap junctions. Therefore, Ca2+ plays a role in the uncoupling of the gap junctions in supp orting cells of the organ of Corti from inside the cells.