Abstract
Tissue distribution of anticancer agents was compared in combination with or without L-623 in S. 180 bearing mice and the pharmacokinetics of 14C-L-623 were studied in S. 180 and Ehrlich carcinoma bearing mice. (1) The concentration of peplomycin, 5-fluorouracil and adriamycin in tumor tissues increased selectively in combination with L-623. (2) Above effects were observed by before or simultaneous administration of L-623. (3) The blood level curves of 14C-L-623 showed a relatively short α-phase and a very long γ-phase. (4) 14C-L-623 distributed highly in the liver and spleen and moderately in the heart, lung, stomach and kidney for a long time. Into tumor tissues, it distributed slowly and reached a considerably high level at 7 to 24 hours after administration and persisted for a week. By multiple daily doses, 14C-L-623 showed accumulation in normal and tumor tissues.
