In vivo distribution of carrier protein/67Ga-complexes.

The uptake of 67Ga as citrate, chloride and complexed by carrier-proteins (lactoferrin and transferrin) has been studied in tumor- and inflammatory lesion-bearing rats. Different uptake patterns are shown by tumors and lesions. 67Ga-transferrin complexes are taken up to the highest extent by tumors and inflammatory lesions. The comparative distribution studies using normal animals indicate a systemic increase of 67Ga uptake by tumor- and lesion-bearing animals which might be of importance in explaining the mechanism of 67Ga accumulation. The role of ionic environment changes and radioactivity concentration by isomorphous ionic replacement is discussed.