BIS-DITHIOCARBAMATES - EFFECTIVE CHELATING-AGENTS FOR MOBILIZATION OFPO-210 FROM RAT

The time dependence of organ distribution and excretion of intravenous ly (iv) injected Po-210 was investigated after the single or repeated administration of N,N'-diethylamine-N-carbodithioate (diethyldithiocar bamate, DDTC) and three bis-dithiocarbamates: ,N'-dimethylethylenediam ine-N,N'-biscarbodithioate (MeTTC), N,N'-diethylethylenediamine-N,N'bi scarbodithioate (EtTTC), and ydroxyethyl)ethylenediamine-N,N'-biscarbo dithioate (HOEtTTC). The biokinetics of iv injected Po-210 was used as a model for the behaviour of Po-210 absorbed into the blood from any other site of entry into the body. The most effective chelating agent was HOEtTTC, which was not only effective when injected subcutaneously (sc) immediately after Po-210, but also 1 h later. Toxic effects of D DTC were observed in a metabolic study when the effect of HOEtTTC was compared with that of DDTC. DDTC caused accumulation of Po-210 in brai n and transiently in liver. When HOEtTTC was administered, the faecal excretion of Po-210 was increased from the very beginning. MeTTC, EtTT C and N-(2,3-dimercaptopropyl)phtalamidic acid (DMPA) were ineffective when the treatment started 1 h after iv injection of Po-210.