Retinal spreading depression induced by photoactivation: involvement of free radicals and potassium

Brain Res. 1999 May 8;827(1-2):221-4. doi: 10.1016/s0006-8993(99)01296-2.

Abstract

The threshold for spreading depression (SD) in chicken retina elicited by rose bengal photoactivation was raised by Trolox (water soluble vitamin E) suggesting the participation of reactive oxygen species in SD. The typical increases in K+ concentration associated with SD were preceded by small K+ oscillations that were more sensitive to photoactivation than was SD. It is hypothesised that all these phenomena could be accounted for by a free-radical mediated transient increase in membrane permeability and that this may be relevant to ischemic brain damage.

MeSH terms

  • Animals
  • Antioxidants / pharmacology
  • Cell Membrane Permeability / drug effects
  • Cell Membrane Permeability / physiology
  • Chickens
  • Chromans / pharmacology
  • Fluorescent Dyes / pharmacology*
  • Free Radicals / metabolism
  • Ischemia / metabolism
  • Ischemia / physiopathology
  • Magnesium Sulfate / pharmacology
  • Membrane Potentials / drug effects
  • Membrane Potentials / physiology
  • Periodicity
  • Photochemistry
  • Potassium Chloride / metabolism*
  • Retina / drug effects
  • Retina / physiology*
  • Rose Bengal / pharmacology*
  • Rubidium / pharmacology

Substances

  • Antioxidants
  • Chromans
  • Fluorescent Dyes
  • Free Radicals
  • Rose Bengal
  • Potassium Chloride
  • Magnesium Sulfate
  • Rubidium
  • 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid