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Updated: Oct 17, 2026

Proteomics to Identify Proteins Interacting with P2X2 Ligand-Gated Cation Channels
Published on: May 18, 2009
The novel pyridoxal-5'-phosphate derivative PPNDS potently antagonizes activation of P2X(1) receptors
G Lambrecht1, J Rettinger, H G Bäumert
1Department of Pharmacology, Biocentre Niederursel, University of Frankfurt, Geb. N260, Marie-Curie-Str. 9, D-60439, Frankfurt, Germany. lambrecht@em.uni-frankfurt.de
Abstract:
Pyridoxal-5'-phosphate-6-(2'-naphthylazo-6'-nitro-4',8'-disulfonat e) (PPNDS) potently antagonized P2X(1) receptor-mediated responses in rat vas deferens (pK(B)=7.43) and Xenopus laevis oocytes (pIC(50)=7. 84). It showed lower (up to 20,000-fold) inhibitory potency on ecto-nucleotidase in Xenopus oocytes and on P2Y(1) receptors in guinea-pig ileum (pA(2)=6.13). PPNDS did not interact with alpha(1A)-adrenoceptors, adenosine A(1) and A(2B), histamine H(1) and muscarinic M(3) receptors. Thus, PPNDS is a novel, specific P2 receptor antagonist and represents the pyridoxal-5'-phosphate derivative with the highest potency at P2X(1) receptors.
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