POM 1, also known as sodium polyoxotungstate and sodium metatungstate, is a novel, potent inhibitor of ecto-nucleoside triphosphate diphosphohydrolases (Ecto-NTPDases). POM 1 exhibits minor selectivity for NTPDase 1 and NTPDase 3 over NTPDase 2, with Ki values being 2.58, 28.8 and 3.26 μM for NTPDase 1 (CD39), NTPDase 2 and NTPDase 3, respectively. Ecto-NTPDases capable of hydrolyzing nucleoside tri- and diphosphates are able to reduce the effective concentration of the released nucleotide, and inhibitors of Ecto-NTPDases can thus serve as valuable tools for amplifying the biological effects triggered by extracellularly released nucleotides.

References:

1. Müller CE, Iqbal J, Baqi Y, et al. Polyoxometalates--a new class of potent ecto-nucleoside triphosphate diphosphohydrolase (NTPDase) inhibitors. Bioorganic & Medicinal Chemistry Letters, 2006, 16(23): 5943-5947.

2. Wall MJ, Wigmore G, Lopatár J, et al. The novel NTPDase inhibitor sodium polyoxotungstate (POM-1) inhibits ATP breakdown but also blocks central synaptic transmission, an action independent of NTPDase inhibition. Neuropharmacology, 2008, 55(7): 1251-1258.