In vivo covalent binding of 17-alpha-OH- and 17-beta-OH- trenbolone to rat liver DNA.
In vivo covalent binding to rat liver DNA was assayed with 2 major metabolites of trenbolone, alpha-OH-trenbolone (alpha-TB) and beta-OH-trenbolone (beta-TB), in male Sprague-Dawley rats. DNA purified by ultracentrifugation in cesium trifluoroacetate showed protein contamination less than 0.4% of DNA by weight. The mean results obtained for the covalent binding indexes were 2.4 +/- 0.3 for alpha-TB and 5.3 +/- 2 for beta-TB. The covalent binding of alpha-TB was linear as a function of dose, which was not the case for beta-TB. The higher affinity of beta-trenbolone for DNA contaminating proteins was not sufficient to explain the difference. When these results are compared with the genotoxicity tests already performed with trenbolone by several authors (almost all completely negative), it may be concluded that the very low levels of binding could not be regarded as responsible for a direct genotoxic action of trenbolone.
Petit
C R
CR
Ecole Nationale Vétérinaire, Laboratoire de toxicologie biochimique et métabolique, Toulouse, France.
Fournier
P A
PA
Rico
A G
AG
Burgat-Sacaze
V
V
de Saqui-Sannes
P
P
D000818:Animals; D004247:DNA / Q000378:metabolism*; D004963:Estrenes / Q000378:metabolism*; D007274:Injections, Intraperitoneal; D008099:Liver / Q000378:metabolism*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D014204:Trenbolone Acetate / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000378:metabolism*
D004963:Estrenes; D004247:DNA; D014204:Trenbolone Acetate