Antifertility and ultrastructural effects of optical isomers of gossypol administered intratesticularly in rats.

This study reports on the effects of optical isomers of gossypol administered intratesticularly on testicular ultrastructure and fertility in rats. Gossypool isomers were administered to adult male rats by daily intratesticular injections for up to two days at a dose of 1200 ugm/testis. The results of this study have demonstrated that the intratesticular injection of racemic and (-) gossypol at a dose of 1200 ugm for 1 or 2 days mimic the effect of gossypol on rat testis after oral administration of 20 to 30 mg dose for 5-7 weeks; (-)-gossypol was found to be 81% effective in inducing mitochondrial sheath damage in the late spermatids of stage VI, VII and VIII tubules compared to 67% for racemic and 7% for (+)-gossypol, the intratesticular injection of (+/-) and (-)-gossypol (1200 ugm/testis, daily for 1 or 2 days) induces complete infertility three weeks after the last injection.