Presynaptic and Ca(2+)-independent PKC subspecies modulates NMDAR1 current.
We have studied the properties of the protein kinase C (PKC) subspecies that modulates the NMDA receptor (NMDAR1). The current through homomeric NMDAR1 expressed in Xenopus oocytes was increased by 200-500% by phorbol ester and also by activation of a metabotropic glutamate receptor (mGluR1) expressed in the same oocytes. This potentiation of the NMDAR1 current was not inhibited by the intracellular injection of EGTA. Intracellular injection of epsilon-PKC, a presynaptic PKC subspecies, potentiated the NMDAR1 current more efficiently that did the Ca(2+)-dependent gamma-PKC, a postsynaptic subspecies of the enzyme. Our findings suggested that the presynaptic NMDA receptor could be potentiated in a Ca(2+)-independent manner by the activation of presynaptic PKC subspecies.
Koga
T
T
Department of Pharmacology, Kobe University School of Medicine, Japan.
Sakai
N
N
Tanaka
C
C
Saito
N
N
D000818:Animals; D002118:Calcium / Q000502:physiology*; D004594:Electrophysiology; D005260:Female; D005998:Glycine / Q000494:pharmacology; D009865:Oocytes / Q000378:metabolism; D010703:Phorbol Esters / Q000494:pharmacology; D011493:Protein Kinase C / Q000378:metabolism*; D018094:Receptors, Metabotropic Glutamate / Q000187:drug effects / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects / Q000378:metabolism*; D017661:Receptors, Presynaptic / Q000187:drug effects / Q000378:metabolism*; D013095:Spermidine / Q000494:pharmacology; D014982:Xenopus laevis
D010703:Phorbol Esters; D018094:Receptors, Metabotropic Glutamate; D016194:Receptors, N-Methyl-D-Aspartate; D017661:Receptors, Presynaptic; D011493:Protein Kinase C; D002118:Calcium; D005998:Glycine; D013095:Spermidine