Activation of protein kinase C inhibits kainate-induced currents in oocytes expressing glutamate receptor subunits

J Neurochem. 1994 Apr;62(4):1639-42. doi: 10.1046/j.1471-4159.1994.62041639.x.

Abstract

The effect of protein kinase C (PKC) activation on maximal kainate (KA)-induced currents was studied in Xenopus oocytes expressing the glutamate receptor (GluR) subunits GluR3, GluR1 + 3, GluR2 + 3, and GluR6. The PKC activator phorbol 12-myristate 13-acetate (PMA) inhibited peak KA responses in a time-dependent manner. The magnitude of inhibition was greatest in GluR6-expressing oocytes. Desensitizing KA currents characterized by a peak, transient current followed by a slower, desensitizing current were observed in oocytes expressing GluR3 and GluR1 + 3 receptors. PMA inhibited the desensitization, and this effect could be observed before PMA's inhibition of peak current amplitude. PMA-mediated inhibition of both desensitization and peak current amplitude was prevented by intracellular injection of the protein kinase C (PKC) inhibitor peptide. These results suggest that the function of GluRs is regulated by PKC-dependent phosphorylation.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Electric Conductivity
  • Enzyme Activation / drug effects
  • Female
  • Gene Expression*
  • Gene Transfer Techniques
  • Kainic Acid / pharmacology*
  • Oocytes / drug effects
  • Oocytes / physiology*
  • Phosphorylation
  • Protein Kinase C / metabolism*
  • Receptors, Glutamate / genetics
  • Receptors, Glutamate / physiology*
  • Tetradecanoylphorbol Acetate / pharmacology
  • Xenopus laevis

Substances

  • Receptors, Glutamate
  • Protein Kinase C
  • Tetradecanoylphorbol Acetate
  • Kainic Acid