188Re(V)-DMSA revisited: preparation and biodistribution of a potential radiotherapeutic agent with low kidney uptake.
Methods of preparation and biodistribution in mice of tin-free 99Tcm(V)-DMSA and 188Re(V)-DMSA, a potential matching pair of radiopharmaceuticals for diagnosis and therapy of certain cancers, are described. Preparation of tin-free 188Re(V)-DMSA (I) is based on reduction with either SO2-releasing compounds like Na2S2O4 (30 mg Na2S2O4, 10 mg DMSA, 1 mg L-ascorbic acid, 37 degrees C, 60 min incubation), Na2S2O5 (as before, 70 degrees C, 15 min incubation), or HBr (0.2 ml 48% HBr, 0.2 ml 7 M HCl, 10 mg DMSA, 1 mg L-ascorbic acid, 70 degrees C, 60 min incubation). I exhibits significantly lower kidney uptake than tin-containing 188Re(V)-DMSA (II) (2-3% and 49% injected dose per gram organ, 1 h post-injection, respectively). HPLC profiles of I and II are similar. DMSA excess in tin-free 188Re(V)-DMSA is not responsible for the low kidney uptake of I. High kidney uptake of II is explained by formation of a mixed 188Re(V)-Sn-DMSA complex in vivo. Age-linked bone uptake in mice dependent on the maturation of the bone is demonstrated for both I and II.
Dadachova
E
E
Radiopharmaceuticals R&D, Australian Nuclear Science and Technology Organization, Menai, NSW.
Chapman
J
J
D000375:Aging; D000818:Animals; D001692:Biological Transport; D001846:Bone Development; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000378:metabolism; D007668:Kidney / Q000000981:diagnostic imaging / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D009942:Organometallic Compounds / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D012211:Rhenium / Q000493:pharmacokinetics / Q000627:therapeutic use; D004113:Succimer / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D019783:Technetium Tc 99m Dimercaptosuccinic Acid / Q000493:pharmacokinetics; D013997:Time Factors; D014001:Tin; D014018:Tissue Distribution
D009942:Organometallic Compounds; D019275:Radiopharmaceuticals; C069609:rhenium(V)dimercaptosuccinic acid; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D012211:Rhenium; D014001:Tin; D004113:Succimer