Androgen regulation of polyamine synthesis in seminal vesicle and in different lobes of the rat prostate.

Endogenous levels of the polyamines putrescine, spermidine, and spermine have been examined in the 10(6) m/s2 supernatant of different lobes of the rat prostate and in the seminal vesicles of castrates, androgen-stimulated castrates, and intact controls. Content of the polyamines varied between the lobes, with spermidine highest in intact animals. After castration, the content of polyamines fell significantly in all lobes but the coagulating gland (CG). Spermidine levels were highest, except in the lateral prostate (LP) and CG, where the content of putrescine was highest. In castrated animals treated with testosterone propionate for 72 h, the amount of the three polyamines examined increased dramatically in the ventral prostate (VP) and moderately in the CG and seminal vesicle (SV). Concerning individual polyamines, spermidine increased significantly in all lobes, while putrescine increased significantly only in the two saccular parts of rat prostate, i.e., CG and SV. Spermidine content decreased significantly in the DP. Major differences in the content of the three polyamines--putrescine, spermidine, and spermine--in the various tissues studied have been found. Moreover, distinct differences among intact, castrated, and testosterone-treated castrated animals have been revealed.

Ornithine decarboxylase and S-adenosylmethionine decarboxylase activity in the accessory sex organs of intact, castrated, and androgen-stimulated castrated rats.

We have studied the activities of ornithine decarboxylase and adenosylmethionine decarboxylase in the 10(6)-m/s2 supernatants of the different lobes of the prostate and the seminal vesicles of castrates, androgen-stimulated castrates, and intact controls. After castration L-ornithine decarboxylase (ODC) and S-adenosyl-L-methionine decarboxylase (AMDC) activities fell in all tissues examined. The induction of kinetics was followed for 72 h after administration of testosterone propionate to castrated rats. AMDC activities increased more rapidly than ODC activities in every tissue studied. Peak activities were reached more rapidly in the dorsal lobe than in the other tissues. ODC activity of the ventral lobe increased linearly for 48 h after stimulation. In the other tissues studied, ODC activity reached a maximum after 24 h and thereafter leveled off or decreased. In conclusion we have found distinct differences in ODC and AMDC activity in various tissues and major differences between treatment groups, with near extinction of activity at castration. In castrates stimulated with testosterone, the between-group differences prevailed but with different patterns of ODC versus AMDC activity. AMDC is seemingly rate-limiting in polyamine synthesis in stimulated tissues, while ODC controls synthesis in tissues from castrated rats.