title: Dual actions of phorbol esters to decrease calcium and potassium conductances of mouse neurons.
abstract: Phorbol esters, which substitute for diacylglycerol to activate protein kinase C, were applied to mouse dorsal root ganglion and cerebral hemisphere neurons in cell culture. The phorbol esters, phorbol 12,13-dibutyrate and 12-O-tetradecanoyl-phorbol-13-acetate, prolonged calcium-dependent action potential duration at resting membrane potential and at more negative membrane potentials but decreased action potential duration following membrane depolarization to less than -45 mV. When calcium and potassium currents were recorded using the single electrode voltage-clamp technique, the phorbol esters were shown to reduce both voltage-dependent calcium and potassium currents. These studies have demonstrated directly that phorbol esters, presumably by activating protein kinase C, can modify more than one membrane conductance in individual neurons.
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D004789:Enzyme Activation; D005727:Ganglia, Spinal / Q000187:drug effects; D007473:Ion Channels / Q000187:drug effects*; D051379:Mice; D015240:Phorbol 12,13-Dibutyrate; D010703:Phorbol Esters / Q000494:pharmacology*; D011188:Potassium / Q000378:metabolism*; D011493:Protein Kinase C / Q000378:metabolism; D013116:Spinal Cord / Q000187:drug effects; D013687:Telencephalon / Q000187:drug effects; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D007473:Ion Channels; D010703:Phorbol Esters; D015240:Phorbol 12,13-Dibutyrate; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate; D011188:Potassium; D002118:Calcium