Removal of hydroxyl radical facilitates Ca2+-dependent [3H]GABA release by peroxynitrite

Brain Res Mol Brain Res. 1998 Nov 12;62(1):96-100. doi: 10.1016/s0169-328x(98)00245-9.

Abstract

We investigated mechanisms for enhancement of peroxynitrite (OONO-; 5 microM)-evoked [3H] gamma-aminobutyric acid (GABA) release. Hydroxyl radical scavengers such as N,N'-dimethylthiourea (DMTU), mannitol, and uric acid, significantly increased OONO--evoked [3H]GABA release, whereas urea showed no effects on the release. Removal of Ca2+ from incubation buffer abolished the enhancement of the release by DMTU, although DMTU showed no effects on the basal release with and without Ca2+ in extracellular space. These results indicate that hydroxyl radical scavengers facilitate OONO--evoked [3H]GABA release dependent on Ca2+.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium / metabolism*
  • Calcium / physiology
  • Cells, Cultured
  • Cerebral Cortex / cytology
  • Dose-Response Relationship, Drug
  • Fetus
  • Free Radical Scavengers / pharmacology
  • Hydroxyl Radical / metabolism*
  • Mannitol / pharmacology
  • Mice
  • Neurons / cytology
  • Neurons / drug effects
  • Nitrates / pharmacology*
  • Thiourea / analogs & derivatives
  • Thiourea / pharmacology
  • Tritium
  • Urea / pharmacology
  • Uric Acid / pharmacology
  • gamma-Aminobutyric Acid / analysis
  • gamma-Aminobutyric Acid / metabolism*

Substances

  • Free Radical Scavengers
  • Nitrates
  • Tritium
  • peroxynitric acid
  • Uric Acid
  • Hydroxyl Radical
  • Mannitol
  • gamma-Aminobutyric Acid
  • 1,3-dimethylthiourea
  • Urea
  • Thiourea
  • Calcium