Turning a spermatogenic wave into a tsunami: synchronizing murine spermatogenesis using WIN 18,446.

The BDADs (bis-[dichloroacetyl]-diamines) are compounds that can inhibit spermatogenesis via blocking the metabolism of vitamin A. We utilized one specific BDAD, WIN 18,446, to manipulate the endogenous production of retinoic acid (RA) in the testis to further investigate the action of this compound on mammalian sperm production. Transient treatment of adult male mice with WIN 18,446 blocked spermatogonial differentiation and induced significant changes in the cycle of the seminiferous epithelium. WIN 18,446 treatment of neonatal mice also blocked spermatogonial differentiation and, followed by injection of RA, induced synchronous spermatogenesis in adulthood. The net result was pulsatile, rather than normal continuous, release of sperm from the seminiferous epithelium. This study describes a novel technique that can enrich for specific germ cell populations within the testis, representing a valuable new tool for studying spermatogenesis.