Effects of PKA and PKC on miniature excitatory postsynaptic currents in CA1 pyramidal cells.
Protein kinases play an important role in controlling synaptic strength at excitatory synapses on CA1 pyramidal cells. We examined the effects of activating cAMP-dependent protein kinase or protein kinase C (PKC) on the frequency and amplitude of miniature excitatory postsynaptic currents (mEPSCs) with perforated patch recording techniques. Both forskolin and phorbol-12,13-dibutryate (PDBu) caused a large increase in mEPSC frequency, but only PDBu increased mEPSC amplitude, an effect that was not observed when standard whole cell recording was performed. These results support biochemical observations indicating that PKC, similar to calcium/calmodulin-dependent protein kinase II, has an important role in controlling synaptic strength via modulation of AMPA receptor function, potentially through the direct phosphorylation of the GluR1 subunit.
Carroll
R C
RC
Department of Psychiatry, University of California, San Francisco, California 94143, USA.
Nicoll
R A
RA
Malenka
R C
RC
D000818:Animals; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D004789:Enzyme Activation; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology*; D006624:Hippocampus / Q000166:cytology / Q000201:enzymology / Q000502:physiology*; D066298:In Vitro Techniques; D018408:Patch-Clamp Techniques; D011493:Protein Kinase C / Q000378:metabolism*; D017966:Pyramidal Cells / Q000201:enzymology / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley
D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C