An evaluation of the tumour affinity of the radioactive cobalt chelate of tallysomycin S10b in lymphoma-bearing mice.
The tumour affinity of the radioactive cobalt chelate of tallysomycin S10b (Tlm S10b), a promising structural analogue of Bleomycin, was assessed using a mouse lymphoma model. The highest concentrations (%dose/gram tissue) were observed in the kidneys, followed by the tumour (4.1%/g 1 h p.i.) at 1 h, 4 h and 48 h. The tumour had the highest concentration among all tissues at 24 h. The biodistribution profile of 60Co-Tlm S10b was distinctly different from that obtained with 60CoCl2, demonstrating the in vivo stability of the chelate. More than half of the chelate (56.8% of the injected dose) was excreted in the urine at 1 h. The highest tumour/non-tumour ratios were obtained for blood (41.3, 4 h), bone (30.5, 4 h) and muscle (29.2, 48 h). Scintigraphy at 24 h, using 57Co-Tlm S10b, showed the tumour, liver, kidney and bladder clearly. The similarities and differences exhibited by Co-Tlm S10b with reference to the literature on cobalt chelates of Bleomycin and naturally occurring tallysomycin (A + B) are discussed.
Veerapandian
R
R
Isotope Division, Cancer Institute, Adyar, Madras, India.
Sivaramakrishnan
V M
VM
D000818:Animals; D001761:Bleomycin / Q000493:pharmacokinetics / Q000031:analogs & derivatives; D008223:Lymphoma / Q000000981:diagnostic imaging* / Q000378:metabolism; D008297:Male; D051379:Mice; D011877:Radionuclide Imaging; D014018:Tissue Distribution
D001761:Bleomycin; C016126:talisomycin