Presynaptic Mechanism for Phorbol Ester-Induced Synaptic Potentiation

摘要: Phorbol ester facilitates transmitter release at a variety of synapses, and the phorbol ester-induced synaptic potentiation (PESP) is model for presynaptic facilitation. To address mechanism underlying PESP, we have made paired whole-cell recordings from giant terminal, calyx Held, its postsynaptic target in medial nucleus trapezoid body rat brainstem slices. potentiated EPSCs without affecting either calcium currents or potassium currents. Protein kinase C inhibitors applied outside injected directly into terminal attenuated PESP. Furthermore, loading synthetic peptide with sequence N-terminal domain Doc2α interacting Munc13–1 (Mid peptide) significantly whereas mutated Mid had no effect. We conclude that facilitatory effect resides downstream influx may involve both protein - interaction.