Neurochemical Research

, Volume 28, Issue 10, pp 1597–1605

P2X7 Receptors in Rat Brain: Presence in Synaptic Terminals and Granule Cells

  • Maria Teresa Miras-Portugal
  • Miguel Díaz-Hernández
  • Lisandro Giráldez
  • Cristina Hervás
  • Rosa Gómez-Villafuertes
  • Raquel P. Sen
  • Javier Gualix
  • Jesús Pintor
Article

DOI: 10.1023/A:1025690913206

Cite this article as:
Miras-Portugal, M.T., Díaz-Hernández, M., Giráldez, L. et al. Neurochem Res (2003) 28: 1597. doi:10.1023/A:1025690913206

Abstract

ATP stimulates [Ca2+]i increases in midbrain synaptosomes via specific ionotropic receptors (P2X receptors). Previous studies have demonstrated the implication of P2X3 subunits in these responses, but additional P2X subunits must be involved. In the present study, ATP and BzATP proved to be able to induce intrasynaptosomal calcium transients in the midbrain synaptosomes, their effects being potentiated when assayed in a Mg2+-free medium. Indeed, BzATP was shown to be more potent than ATP, and their effects could be inhibited by PPADS and KN-62, but not by suramin. This activity profile is consistent with the presence of functional P2X7 receptors in the midbrain terminals. The existence of presynaptic responses to selective P2X7 agonists could be confirmed by means of a microfluorimetric technique allowing [Ca2+]i measurements in single synaptic terminals. Additionally, the P2X7 receptor protein could be identified in the midbrain synaptosomes and in axodendritic prolongations of cerebellar granule cells by immunochemical staining.

P2X7, ATP receptors presynaptic receptors synaptic terminals 

Copyright information

© Plenum Publishing Corporation 2003

Authors and Affiliations

  • Maria Teresa Miras-Portugal
    • 1
  • Miguel Díaz-Hernández
    • 1
  • Lisandro Giráldez
    • 1
  • Cristina Hervás
    • 1
  • Rosa Gómez-Villafuertes
    • 1
  • Raquel P. Sen
    • 1
  • Javier Gualix
    • 1
  • Jesús Pintor
    • 1
  1. 1.Departamento de Bioquímica y Biologia Molecular IV, Facultad de VeterinariaUniversidad Complutense de MadridMadridSpain

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