On the Mechanisms of ⁶⁷Ga and ⁵⁹Fe Uptake by Tumors

The uptake of ⁶⁷Ga-citrate and ⁵⁹Fe-citrate in the presence or absence of gallium and iron carriers, was studied on DSsarcoma-bearing rats. Differences of uptake pattern were observed with both radionuclides. The tumor uptake of ⁶⁷Ga is greatly affected by both carriers while ⁵⁹Fe uptake is independent of the presence of carriers. The role of isotopic dilution, ionic competition, and the probable presence of high and low affinity binding sites in this phenomenon are discussed.

Die Aufnahme von ⁶⁷Ga-Zitrat und ⁵⁹Fe-Zitrat, mit und ohne Gallium-und Eisenträger, wurde in Ratten mit DSSarkom untersucht. Beide Radionuklide zeigen unterschiedliche Aufnahmen. Beide Träger beeinflussen die Speicherung von ⁶⁷Ga-Zitrat stark, jedoch nicht jene der ⁵⁹Fe-Zitrat Aufnahme. Die Rolle der isotopischen Verdünnung, des isomorphen Ionenaustauschs und des wahrscheinlichen Auftretens von „high” und „low affinity” Bindungsstellen wird diskutiert.

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