Presynaptic enhancement of synaptic transmission in hippocampal cell cultures by phorbol esters.
The calcium-diacyglycerol activated protein kinase (C kinase) plays an important role in synaptic plasticity, and possibly in long-term potentiation (LTP). We have found that phorbol esters, which activate this protein kinase, increase the frequency of miniature excitatory postsynaptic currents (mEPCs) in hippocampal cell cultures. An analysis of distributions of these miniature synaptic currents shows that amplitudes, and thus postsynaptic function, are not influenced by phorbol esters. Synaptic transmission is therefore enhanced by phorbol esters at a presynaptic locus. The method of analysis employed here is applicable to a broad range of situations involving modification of synaptic transmission in the mammalian central nervous system.
Finch
D M
DM
Department of Neurology, University of California, Los Angeles 90024.
Jackson
M B
MB
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002478:Cells, Cultured; D004622:Embryo, Mammalian; D005071:Evoked Potentials / Q000187:drug effects; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice; D009474:Neurons / Q000187:drug effects / Q000502:physiology; D010703:Phorbol Esters / Q000494:pharmacology*; D013569:Synapses / Q000187:drug effects / Q000502:physiology*; D009435:Synaptic Transmission / Q000187:drug effects*; D019789:Tetraethylammonium; D013757:Tetraethylammonium Compounds / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology
D010703:Phorbol Esters; D013757:Tetraethylammonium Compounds; D013779:Tetrodotoxin; D019789:Tetraethylammonium