Kinetic analysis and comparison of uptake, distribution, and excretion of V-48-labeled compounds in rats

Vanadium has been found to be orally active in lowering plasma glucose levels; thus it provides a potential treatment for diabetes mellitus. Bis(maltolato)oxovanadium(rv) (BMOV) is a well-characterized organovanadium compound that has been shown in preliminary studies to have a potentially useful absorption profile. Tissue distributions of BMOV compared with those of vanadyl sulfate (VS) were studied in Wistar rats by using V-48 as a tracer. In this study, the compounds were administered in carrier-added forms by either oral gavage or intraperitoneal injection. Data analyzed by a compartmental model, by using simulation, analysis, and modeling (i.e., SAAM II) software, showed a pattern of increased tissue uptake with use of V-48-BMOV compared with (VS)-V-48. The highest V-48 concentrations at 24 h after gavage were in bone, followed by kidney and liver. Most ingested V-48 was eliminated unabsorbed by fecal excretion. On average, V-48 concentrations in bone, kidney, and liver 24 h after oral administration of V-48-BMOV were two to three times higher than those of (VS)-V-48, which is consistent with the increased glucose-lowering potency of BMOV in acute glucose lowering compared with VS.