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Cell and Tissue Research

, 334:199 | Cite as

Distribution of ectonucleotidases in the rodent brain revisited

  • David Langer
  • Klaus Hammer
  • Patrycja Koszalka
  • Jürgen Schrader
  • Simon Robson
  • Herbert Zimmermann
Regular Article

Abstract

Nucleotides comprise a major class of signaling molecules in the nervous system. They can be released from nerve cells, glial cells, and vascular cells where they exert their function via ionotropic (P2X) or metabotropic (P2Y) receptors. Signaling via extracellular nucleotides and also adenosine is controlled and modulated by cell-surface-located enzymes (ectonucleotidases) that hydrolyze the nucleotide to the respective nucleoside. Extracellular hydrolysis of nucleotide ligands involves a considerable number of enzymes with differing catalytic properties differentially affecting the nucleotide signaling pathway. It is therefore important to investigate which type of ectonucleotidase(s) contributes to the control of nucleotide signaling in distinct cellular and physiological settings. By using a classical enzyme histochemical approach and employing various substrates, inhibitors, and knockout animals, we provide, for the first time, a comparative analysis of the overall distribution of catalytic activities reflecting four ectonucleotidase families: ecto-5′-nucleotidase, alkaline phosphatases, ectonucleoside triphosphate diphosphohydrolases (E-NTPDases), and ectonucleotide pyrophyphatases/phosphodiesterases (E-NPPs). We place into perspective the earlier literature and provide novel evidence for a parenchymal localization of tissue non-specific alkaline phosphatase, E-NPPs, and E-NTPDases in the mouse brain. In addition, we specify the location of ectonucleotidases within the brain vasculature. Most notably, brain vessels do not express ecto-5′-nucleotidase. The preponderance of individual enzymes differs considerably between brain locations. The contribution of all types of ectonucleotidases thus needs to be considered in physiological and pharmacological studies of purinergic signaling in the brain.

Keywords

Alkaline phosphatase ATP Brain Ectonucleotidase Ecto-5′-nucleotidase Mouse (C57BL/6; CD73 Knockout; 129 Sv; NTPDase1 null) 

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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • David Langer
    • 1
  • Klaus Hammer
    • 1
  • Patrycja Koszalka
    • 2
  • Jürgen Schrader
    • 2
  • Simon Robson
    • 3
  • Herbert Zimmermann
    • 1
  1. 1.Institute of Cell Biology and Neuroscience, BiocenterGoethe University Frankfurt am MainFrankfurtGermany
  2. 2.Department of Cardiovascular PhysiologyHeinrich Heine University DuesseldorfDuesseldorfGermany
  3. 3.Department of Medicine, Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonUSA

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