Reduction of testicular testosterone levels in rats by prostaglandin E2.

The effect of intratesticular administration of prostaglandin (PG) E2, PGF2 alpha and PGD2 on rat testes testosterone levels were studied. The intratesticular administration of PGE2 or PGD2 markedly decreased the testicular testosterone levels in rats. The decrease of testosterone concentration in rat testis was not obtained by PGF2 alpha. In the incubation experiment, PGE2 reduced the release of testosterone from fragment rat testis. These results suggest that PGE2 acts on androgen biosynthesis in rat testes.