Study of the protective effect of an anabolic steroid, 19-nortestosterone phenylpropionate (19-NTPP) on the fatty liver induced by high doses of rifampicin in the rat.

The purpose of this work was to study if the steatogenic effect on the liver of Rifampicin, which is an inhibitor of the RNA polymerases DNA dependent in bacteria, can be prevented by an anabolic steroid: 19 nortestosterone phenylproprionate (19-NTPP) which probably stimulates the RNA polymerase activity in eukariotic cells. 19-NTPP (25 mg/kg/24 h, i.p.) was administered to male and both intact and ovariectomized female rats for 8 days prior to the administration of Rifampicin (400 mg/kg/24 h for 8 days). In male rats, 19-NTPP does not prevent the Rifampicin-induced fatty liver. On the contrary, in female rats, 19-NTPP exerts a partial protective effect in intact as well as in ovariectomized animals. These results show that the protective effect of 19-NTPP against Rifampicin fatty liver is less complete and little specific, comparated to the protective effect obtained against another steatogenic compound in female rats: alpha-Amanitin, which is a potent inhibitor of RNA polymerase II in eukariotic cells. In conclusion, the inhibitor effect of Rifampicin on the hepatic apolipoprotein biosynthesis appears as less specific and more intricate than the comparable effect of alpha-Amanitin.