POSTNATAL-DEVELOPMENT OF ORNITHINE DECARBOXYLASE AND POLYAMINES IN THE MOUSE KIDNEY - INFLUENCE OF TESTOSTERONE

The role of ornithine decarboxylase (ODC) and polyamines in kidney gro wth during the postnatal development of mice and the influence of test osterone were investigated. A marked sexual dimorphism in renal size w as evident after the 3rd week of life, corresponding with the rise in circulating testosterone and the increase in renal ODC and urinary exc retion of putrescine in male mice. Renal putrescine and spermidine gra dually decreased during the first 3 weeks of life and did not correlat e with ODC activity. Treatments with alpha-difluoromethylornithine, an d ODC-specific inhibitor, and the antiandrogen flutamide during weeks 4 and 5 showed that both compounds decreased renal ODC activity but on ly flutamide impaired kidney growth, suggesting that renal growth in m ice is regulated by androgens but is independent of the induction of O DC activity.