1988 Volume 5 Pages 95-99
Although there were reports that vanadium (V) plays some role in bone formation, its relation to the ossification is not clear now. For this reason, we were interested to study the nutritional role of V, and investigated the distribution of vanadium-48 (48V) in rats and their bones in comparison to that of phosphorus-32 (32P). In whole-body autoradiograms of Wistar rats injected with 48V and 32P, 48V was uptaked in all bones as well as 32P. 48V and 32P were uptaked in bone of Wistar rats more than that of ODS rats (these rats having an osteogenic命 disorder).The autoradiograms of the femur in Wistar and ODS rats showed that both nuclids were distributed in the epiphysis. These results suggested that V particpated in ossification through the same mechanism as P.
We also synthesized [48V] vanadyl pheophorbide chelate (48V(IV)O-Pheo) and examined it to apply as a useful positron radiopharmaceutical for tumor diagnosis, since 48V emitted positron and pheophorbide had photodynamic actions and an affinity to tumors. At 24h after injection, high uptake of 48V(IV)O-Pheo was observed in FM3A, MH 134 and S 180 tumors. In the autoradiograms of mice bearing FM3A tumor, 48V(IV)O-Pheo showed the image of tumor most distinctly at 24h when compared with other 48V compounds. These results demonstrated that 48V(IV)O-Pheo may be useful as a new radiophamaceutical for tumor diagnosis, which can be conjugated with the photodynamic therapy using light and pheophorbide.