Sodium orthovanadate

Potent inhibitor of alkaline phosphatase and tyrosine phosphates. Regarding decavanadate: across the pH range of 1-13, simple aqueous solutions of [VO₄]^3- ion involve a dozen or more ionic species, both monomeric and oligomeric, whose abundances depend strongly on pH and [VO₄]^3- concentration. At pH 3.75 a stable complex can be prepared (see below in Fohr et al.) which contains ten vanadium atoms and hence is a decavanadate ion. When diluted to pH 7.2, the decavanadate species has a half-life time of about 2 hours. Fohr et al., also provide directions for generating control solutions of mixed vanadate complexes in which decavanadate is absent and monomeric orthovanadate is present. Decavanadate inhibits inositol 1,4,5-trisphosphate- (IP₃) induced calcium release from permeabilized endocrine cells and the binding of [³H]IP₃ to its receptor in cerebellar and adrenal cortical membranes.