Sodium-sensitive cocaine binding to rat striatal membrane: possible relationship to dopamine uptake sites

J Neurochem. 1983 Jul;41(1):172-8. doi: 10.1111/j.1471-4159.1983.tb13666.x.

Abstract

In rat striatal membranes, NaCl induced a twofold increase in the maximal number of cocaine binding sites but did not alter the affinity of these sites for cocaine. This effect was concentration-dependent, specific to sodium ions, and occurred in membranes prepared from corpus striatum but not from other brain regions. Lesions with 6-hydroxydopamine but not with kainic acid eliminated the sodium-induced increase in binding and produced a decrease in the Bmax of binding measured in the presence of NaCl. The capacity of a series of drugs to interfere with Na+-dependent cocaine binding correlated well with their capacity to inhibit [3H]dopamine uptake into rat striatal synaptosomes. The present results suggest that Na+-dependent cocaine binding sites are localized presynaptically on dopaminergic nerve terminals in corpus striatum, and may be related to dopamine uptake sites.

MeSH terms

  • Animals
  • Binding Sites
  • Cell Membrane / metabolism
  • Cocaine / metabolism*
  • Corpus Striatum / metabolism*
  • Dopamine / metabolism*
  • Intracellular Membranes / metabolism
  • Kinetics
  • Male
  • Rats
  • Rats, Inbred Strains
  • Receptors, Dopamine / metabolism*
  • Salts
  • Sodium / pharmacology*
  • Synaptosomes / metabolism

Substances

  • Receptors, Dopamine
  • Salts
  • Sodium
  • Cocaine
  • Dopamine