BINDING OF 3H-DMBA WITH BIOPOLYMERS OF MOTHER AND FETUS TISSUES IN RATS DURING TRANSPLACENTAL CARCINOGENESIS

The aim of the study was to establish regularities of activated 3H-7,12-dimetilbenz(a)antratcene (DMBA) translocation in the major biopolymers of target and non-target organs at the initiation stage of transplacental carcinogenesis. DMBA was administered i.p. to rats on the 21th day of the pregnancy. Analysis of liver and kidney tissues of mothers, as well as liver, kidney, and brain of offspring was performed at temporal points of 1 hr to 14 days after single carcinogen administration. A regular, but transient non-specific accumulation of DMBA-radioactivity in the lipid fraction mainly embryonic tissues was observed during the first 6 hrs after administration of the labeled carcinogen. By 6 hrs, the maximum increase of label in RNA of embryonic brain and kidney (target organ for tumor induction) was observed and then, from 6 to 12 hrs, an increase occurred in the number of radioactive DNA adducts of fetus that was maintained for 24 hrs in these tissues. Increased accumulation of label in proteins of embryonic kidney was recorded from 6 to 24 hrs, and brain - from 12 to 24 hrs after administration of 3H-DMBA and on the 7th day in proteins of these organs of newborn rats.