Developmental change in the modulation of acetylcholine receptor channel by protein kinase C activation in Xenopus embryonic muscle cells.
Protein phosphorylation is important in synaptic transmission and plasticity. We report here that phorbol 12-myristate 13-acetate (TPA), a protein kinase C (PKC) activator, enhances the postsynaptic response at developing neuromuscular junctions by increasing the open time of embryonic acetylcholine (ACh) channels at earlier stages of cultured myocytes. Compared with day-1 cultures, the effects of TPA declined or disappeared on day-3 cultures. Adenosine 5'-triphosphate (ATP) which is co-stored and co-released with ACh at motor nerve terminals and is reported to enhance spontaneous synaptic currents by the activation of PKC, also shows similar developmental changes in the modulation of embryonic ACh channels in Xenopus embryonic myocytes.
Fu
W M
WM
Pharmacological Institute, College of Medicine, National Taiwan University, Taipei, ROC.
Lin
J L
JL
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D004625:Embryo, Nonmammalian; D004789:Enzyme Activation / Q000187:drug effects / Q000502:physiology; D007473:Ion Channels / Q000187:drug effects / Q000378:metabolism*; D009132:Muscles / Q000187:drug effects / Q000196:embryology / Q000378:metabolism*; D009469:Neuromuscular Junction / Q000187:drug effects; D009474:Neurons / Q000201:enzymology / Q000378:metabolism; D011493:Protein Kinase C / Q000378:metabolism*; D011950:Receptors, Cholinergic / Q000187:drug effects / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014981:Xenopus
D007473:Ion Channels; D011950:Receptors, Cholinergic; D000255:Adenosine Triphosphate; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate