TPP+ accumulation in rat brain synaptosomes as a probe for Na+ channels

Eur J Pharmacol. 1986 Dec 16;132(2-3):289-93. doi: 10.1016/0014-2999(86)90618-7.

Abstract

Tetraphenylphosphonium (TPP+) accumulation in rat brain synaptosomes was measured in the presence of various stimuli. TPP+ accumulation was sensitive to an increase of extracellular K+ or to the presence of Na+ channel neurotoxins. Examination of the effects of drugs with different physico-chemical properties on TPP+ accumulation showed that there was no effect under low and high K+ conditions; pimozide, flunarizine and buterizine were active in the presence of veratridine or scorpion venom. These results were compared to data obtained for the specific binding of [3H]BTX-B, a selective marker for the Na+ channel. It can be concluded that certain drugs, although active on [3H]BTX-B binding, are not necessarily identified when TPP+ is used as probe.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Batrachotoxins / pharmacology
  • Brain Chemistry / drug effects*
  • Female
  • In Vitro Techniques
  • Ion Channels / drug effects*
  • Onium Compounds*
  • Organophosphorus Compounds*
  • Potassium / physiology
  • Rats
  • Rats, Inbred Strains
  • Sodium / metabolism*
  • Synaptosomes / metabolism*

Substances

  • Batrachotoxins
  • Ion Channels
  • Onium Compounds
  • Organophosphorus Compounds
  • Sodium
  • Potassium
  • tetraphenylphosphonium