Glutamate receptors as targets of protein kinase C in the pathophysiology and treatment of animal models of mania

Neuropharmacology. 2009 Jan;56(1):47-55. doi: 10.1016/j.neuropharm.2008.08.015. Epub 2008 Aug 22.


Considerable biochemical evidence suggests that the protein kinase C (PKC) signaling cascade may be a convergent point for the actions of anti-manic agents, and that excessive PKC activation can disrupt prefrontal cortical regulation of thinking and behavior. To date, however, brain protein targets of PKC's anti-manic effects have not been fully identified. Here we showed that PKC activity was enhanced in the prefrontal cortex of animals treated with the psychostimulant amphetamine. Phosphorylation of MARCKS, a marker of PKC activity, was increased in the prefrontal cortex of animals treated with the psychostimulant amphetamine, as well as in sleep-deprived animals (another animal model of mania), but decreased in lithium-treated animals. The antidepressant imipramine, which shows pro-manic properties in patients with bipolar disorder (BPD), also enhanced phospho-MARCKS in prefrontal cortex in vivo. We further explored the functional targets of PKC in mania-associated behaviors. Neurogranin is a brain-specific, postsynaptically located PKC substrate. PKC phosphorylation of neurogranin was robustly increased by pro-manic manipulations and decreased by anti-manic agents. PKC phosphorylation of the NMDA receptor site GluN1S896 and the AMPA receptor site GluA1T840 was also enhanced in the prefrontal cortex of animals treated with the antidepressant imipramine, as well as in behaviorally sleep-deprived animals, in striking contrast to the reduced activity seen in lithium-treated animals. These results suggest that PKC may play an important role in regulating NMDA and AMPA receptor functions. The biochemical profile of the PKC pathway thus encompasses both pro- and anti-manic effects on behavior. These results suggest that PKC modulators or their intracellular targets may ultimately represent novel avenues for the development of new therapeutics for mood disorders.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amphetamine / pharmacology
  • Amphetamine / therapeutic use
  • Animals
  • Antidepressive Agents, Tricyclic / pharmacology
  • Antidepressive Agents, Tricyclic / therapeutic use*
  • Bipolar Disorder / drug therapy*
  • Bipolar Disorder / pathology
  • Bipolar Disorder / physiopathology*
  • Cell Membrane / drug effects
  • Cell Membrane / metabolism
  • Central Nervous System Stimulants / pharmacology
  • Central Nervous System Stimulants / therapeutic use
  • Disease Models, Animal
  • Imipramine / pharmacology
  • Imipramine / therapeutic use
  • Intracellular Signaling Peptides and Proteins / metabolism
  • Lithium Chloride / pharmacology
  • Lithium Chloride / therapeutic use
  • Male
  • Membrane Proteins / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Myristoylated Alanine-Rich C Kinase Substrate
  • Neurogranin / metabolism
  • Phosphorylation / drug effects
  • Prefrontal Cortex / drug effects
  • Prefrontal Cortex / metabolism
  • Protein Kinase C / metabolism*
  • Rats
  • Rats, Inbred WKY
  • Receptors, Glutamate / metabolism*
  • Sleep Deprivation


  • Antidepressive Agents, Tricyclic
  • Central Nervous System Stimulants
  • Intracellular Signaling Peptides and Proteins
  • Marcks protein, mouse
  • Marcks protein, rat
  • Membrane Proteins
  • Receptors, Glutamate
  • Myristoylated Alanine-Rich C Kinase Substrate
  • Neurogranin
  • Amphetamine
  • Protein Kinase C
  • Lithium Chloride
  • Imipramine