Ornithine decarboxylase activity during neonatal development of the rat ventral prostate

The relationship between ornithine decarboxylase activity and growth has been examined in ventral prostates from rats aged 2--60 weeks. The incorporation of [125I]iododeoxyuridine in vitro was used to assess DNA-synthetic activity. During 2--7 weeks post-partum ornithine decarboxylase activity/prostrate and the protein content and wet weight increased exponentially. In contrast, the incorporation of [125I]iododeoxyuridine/prostate fell during the first 4 weeks. This decline was reversed at about the time when the systemic concentrations of gonadal androgens start to rise. After 10 weeks post-partum the incorporation of [1252]iododeoxyuridine/prostate and ornithine decarboxylase activity/prostate levelled off, whereas the DNA and protein content of the prostate continued to increase at a slow rate.