Voltage-dependent GABA-induced modulation of calcium currents in chick sensory neurons

Neurosci Lett. 1989 Oct 23;105(1-2):113-9. doi: 10.1016/0304-3940(89)90021-9.

Abstract

Externally applied gamma-aminobutyric acid (GABA) quickly and reversibly reduces by 60% voltage activated Ca2+ currents in chick dorsal root ganglion cells. This action is antagonized by depolarization, with characteristic time and voltage requirements. Intracellular perfusion with guanosine 5'-O-(3-thiotriphosphate) (GTP gamma S) or guanosine 5'-O-(2-thiodiphosphate) (GDP beta S) mimicks and blocks the GABA effect, respectively. A 3-state model describing the reactions involved is proposed.

MeSH terms

  • Animals
  • Calcium Channels / drug effects
  • Calcium Channels / metabolism*
  • Chick Embryo
  • Ganglia, Spinal / cytology
  • Ganglia, Spinal / drug effects
  • Guanosine 5'-O-(3-Thiotriphosphate) / pharmacology
  • Guanosine Diphosphate / analogs & derivatives
  • Guanosine Diphosphate / pharmacology
  • Membrane Potentials / drug effects
  • Neurons, Afferent / drug effects
  • Neurons, Afferent / metabolism*
  • Thionucleotides / pharmacology
  • gamma-Aminobutyric Acid / pharmacology*

Substances

  • Calcium Channels
  • Thionucleotides
  • Guanosine Diphosphate
  • Guanosine 5'-O-(3-Thiotriphosphate)
  • gamma-Aminobutyric Acid
  • guanosine 5'-O-(2-thiodiphosphate)