Effects of female sex hormones on polyamine-oxidizing enzyme activities and polyamine concentrations in immature rat uterus and liver

17 beta-estradiol (E(2)) and progesterone (P) treatment of immature female rats (10 mu g/100 g body weight) respectively resulted in 1.38-fold (p < 0.02) and 1.42-fold (p < 0.02) increase in the uterine polyamine oxidase activity, and 2.45-fold (p < 0.001) and 1.43-fold (p < 0.02) increase in the uterine diamine oxidase activity, as compared to the controls. E(2) caused a 5-fold (p < 0.05) and a 1.36-fold (p < 0.05) increase in putrescine and spermidine concentration respectively in rat uterus. Increases of 1.7-fold (p < 0.02) and 1.6-fold (p < 0.05) in putrescine and spermine concentration were determined in the P-treated uterus, as compared to the controls. The spermidine/spermine ratio, which is regarded as an index of growth rate, was higher in the E(2)-treated uterus and lower in the P-treated uterus than in the control uterus. No statistically significant hormonal effects were estimated in the immature liver. The data reported suggest the possibility of an involvement of polyamine-oxidizing enzymes in the modulation of polyamine concentrations in rat uterus by the female sex hormones.