Modulation of Ca2+ channels by protein kinase C in rat central and peripheral neurons: disruption of G protein-mediated inhibition

Neuron. 1993 Aug;11(2):305-20. doi: 10.1016/0896-6273(93)90186-u.


Activation of protein kinase C (PKC) reduced G protein-dependent inhibition of Ca2+ channels by glutamate, GA-BAB, adenosine, muscarinic, alpha-adrenergic, and LHRH receptors in a variety of central and peripheral neurons. PKC stimulation also relieved the inhibitory effect of internal GTP gamma S and reduced tonic G protein-mediated inhibition observed with internal GTP in the absence of transmitter receptor agonist. Basal Ca2+ channel currents were enhanced by PKC stimulation in most neurons studied. The PKC-induced enhancement of basal current was voltage dependent, and enhanced currents displayed altered kinetics. Inhibition of G proteins with GDP beta S attenuated the PKC-induced enhancement of basal Ca2+ channel current. These results show that PKC regulates the inhibitory effects of G proteins, possibly by disrupting the coupling of G proteins to Ca2+ channels. The PKC-induced enhancement of Ca2+ channel current results, at least in part, from the removal of tonic G protein-mediated inhibition.

Publication types

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

MeSH terms

  • Animals
  • Brain / cytology
  • Brain / metabolism*
  • Calcium Channels / drug effects*
  • Calcium Channels / metabolism
  • Electric Conductivity
  • GTP-Binding Proteins / physiology
  • Neural Inhibition / drug effects
  • Neurons / drug effects
  • Neurons / metabolism*
  • Neurotransmitter Agents / pharmacology
  • Peripheral Nerves / cytology
  • Peripheral Nerves / metabolism*
  • Protein Kinase C / pharmacology*
  • Rats


  • Calcium Channels
  • Neurotransmitter Agents
  • Protein Kinase C
  • GTP-Binding Proteins