Evidence for an in vivo and in vitro modulation of endogenous cortical GABA release by alpha-glycerylphosphorylcholine

Neurochem Res. 1996 May;21(5):547-52. doi: 10.1007/BF02527751.

Abstract

The effects of alpha-glycerylphosphorylcholine (alpha-GPC) on endogenous cortical GABA release were studied both in vivo and in vitro. In freely moving rats, equipped with epidural cups, alpha-GPC (30-300 mg/kg i.p.) increased GABA release. This effect was potentiated by atropine, both systematically administered (5 mg/kg i.p.) and locally applied (1.4 microM), but not by mecamylamine (4 mg/kg i.p.). The alpha-GPC-induced increase in GABA release was abolished in rats pretreated with the alpha 1 receptor antagonist prazosin (14 micrograms/kg i.p.). In cortical slices alpha-GPC (0.4 mM) increased the spontaneous GABA efflux. This effect was abolished by tetrodotoxin (0.5 microM) and prazosin (1 microM), but not by atropine (0.15 microM) or mecamylamine (2.5 microM). These results indicate that the facilitatory response by alpha-GPC on GABA release does not depend on a direct activation of either muscarinic or nicotinic receptors, but suggest the involvement of the noradrenergic system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Atropine / pharmacology
  • Cerebral Cortex / drug effects
  • Cerebral Cortex / metabolism*
  • Drug Synergism
  • Glycerylphosphorylcholine / administration & dosage
  • Glycerylphosphorylcholine / pharmacology*
  • In Vitro Techniques
  • Injections, Intraperitoneal
  • Kinetics
  • Male
  • Mecamylamine / pharmacology
  • Prazosin / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Tetrodotoxin / pharmacology
  • gamma-Aminobutyric Acid / metabolism*

Substances

  • Tetrodotoxin
  • gamma-Aminobutyric Acid
  • Glycerylphosphorylcholine
  • Mecamylamine
  • Atropine
  • Prazosin