IN-VIVO EFFECTS OF PEROXOVANADIUM COMPOUNDS IN BB RATS

Peroxovanadium compounds, each containing an oxo ligand, one or two pe roxo anions, and an ancillary ligand in the inner coordination sphere of vanadium, were synthesized, crystallized and characterized by V-51 NMR as > 95% pure. They markedly decreased plasma glucose in insulin-d eprived diabetic BE rats, with a nadir occurring between 60 and 100 mi n after intravenous, intraperitoneal or subcutaneous administration. P lasma glucose was reduced after oral administration in insulin-treated and in insulin-deprived BE rats. When compared to sodium orthovanadat e, peroxovanadium compounds exhibited a markedly greater potency on a molar basis, and in relation to their toxicity. The in vivo potency ca n be predicted by the degree of phosphotyrosine phosphatase inhibition observed in vitro. These are the first agents other than insulin that can acutely and markedly reduce plasma glucose in hypoinsulinemic dia betic BE rats.