Abstract
In order to investigate the tumor affinity radioisotopes, vanadium (V-48), niobium (Nb-95), tantalum (Ta-182), arsenic (As-74) and antimony (Sb-124) —the elements of group V in the periodic table—were examined, using the rats which were subcutaneously transplanted with Yoshida sarcoma. Six preparations, 48VO2Cl, 95Nb-oxalate, 182Ta-oxalate, Na2H74AsO4 (Na2HAsO40.008μg), Na2HAsO4 (Na2HAsO41 mg) and124Sb-chloride were injected intravenously to each group of tumor bearing rats. These rats were sacrificed at various periods after injection of each preparation: 3 hours, 24 hours and 48 hours in all preparations. The radioactivities of the tumor, blood, muscle, liver, kidney and spleen were measured by a well-type scintillation counter, and retention values in every tissue including the tumor were calculated (in percent of administered dose per g-tissue weight) .
95Nb-oxalate had considerably strong affinity for the malignant tumor.48VO2Cl, 182Ta-oxalate, Na2H74AsO4and124Sb-chloride did not have any affinity for the malignant tumor. But48VO2Cl had fairly strong affinity for the kidney, Na2H74AsO4had very strong affinity for blood-corpuscles and strong affinity for the spleen.182Ta-oxalate and124Sb-chloride did not have any affinity for the organs and182Ta-oxalate was slowly excreted and124Sb-chloride was rapidly excreted in urine.
