5-HT1A receptor-mediated activation of high-affinity GTPase in rat hippocampal membranes

Eur J Pharmacol. 1995 Feb 15;288(3):385-8. doi: 10.1016/0922-4106(95)90053-5.


GTP hydrolyzing activity was assayed by measuring the amount of 32P(i) released from 0.3 microM [gamma-32P]GTP in the membranes prepared from rat brain. 5-Hydroxytryptamine (5-HT) stimulated the high-affinity GTPase activity in hippocampus, but not in striatum, in a concentration-dependent manner with an EC50 value of 18 nM and maximal percent stimulation of 13.9%. This response was mimicked by (+/-)-8-hydroxy-2-(di-n-propylamino)tetralin [(+/-)-8-OH-DPAT], but not by (+/-)-1-(2,5-dimethoxy-4-iodophyenyl)-2-aminopropane [(+/-)-DOI]. These results suggest that 5-HT-stimulated high-affinity GTPase activity of the GTP-binding protein(s) is mediated via 5-HT1A receptor subtype in the rat hippocampus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 8-Hydroxy-2-(di-n-propylamino)tetralin / pharmacology
  • Animals
  • Dose-Response Relationship, Drug
  • Enzyme Activation
  • GTP Phosphohydrolases / metabolism*
  • GTP-Binding Proteins / metabolism
  • Guanosine Triphosphate / pharmacology
  • Hippocampus / enzymology*
  • In Vitro Techniques
  • Male
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Serotonin / physiology*
  • Serotonin / pharmacology


  • Receptors, Serotonin
  • Serotonin
  • 8-Hydroxy-2-(di-n-propylamino)tetralin
  • Guanosine Triphosphate
  • GTP Phosphohydrolases
  • GTP-Binding Proteins