Effects of novel acetylenic and allenic steroids on the rat prostate.

Novel acetylenic and allenic steroid analogs previously have been synthesized in this laboratory and were shown to be potent irreversible inhibitors of delta5-3-ketosteroid isomerase from P. Testosteroni. This bacterial enzyme catalyzes the conversion of delta5-3-ketosteroids to the corresponding delta4-3-ketosteroids. These isomerizations are key steps in the mammalian biosynthesis of steroid hormones, and it was hoped that the acetylenic and allenic steroid analogs migh inhibit androgen biosynthesis. We have now shown that these compounds cause a significant and dose-dependent decrease in the wet weight of both ventral and dorsal lateral prostate in the mature male rat.