Reversible inhibition of spermatogenesis by danazol with combination of testosterone enanthate in rabbit

Testis functions and sexual potentia in langur monkey treated with a combination steroidal contraceptive formulation

Administration of a combination formulation of danazol (100 mg/day; oral) plus testosterone enanthate (TE) (50 mg/15 days; i.m.) for 30 to 60 days in adult male langur monkeys resulted in the reversible suppression of testicular function without affecting the sexual potentia. Testicular weight and volume decreased significantly along with the mass atrophy of germinal epithelium and impaired morphology of Leydig and Sertoli cells. A conspicuous shrinkage of seminiferous tubules, Leydig cell nuclei and Sertoli cell nuclei was noted. Elevation of testicular cholesterol, total lipids, glycogen and phosphatases activity with the depletion of total proteins, nucleic acid, sialic acid and fructose was noteworthy. All changes were maintained during maintenance dose studies (danazol: 50 mg/day; oral plus TE: 50 mg/15 days; i.m.) for 60 days. Resumption of all measures to normal was evident following 120 days of recovery. It can be concluded that the exogenous TE substitutes the serum testosterone levels to maintain extratesticular androgen actions even after interference by danazol of Leydig cell function along with spermatogenesis inhibition.

Orally administered ketoconazole rapidly appears in seminal plasma and suppresses sperm motility

Ketoconazole has been shown to exert spermatostatic effects in vitro on ejaculated dog, monkey, and human spermatozoa. Oral administration of the compound to adult male beagle dogs (50-246 mg/kg) or rhesus monkeys (85-100 mg/kg) was associated with a decline in motility of sperm in ejaculates obtained after dosing. In dogs the decline in sperm motility was correlated with the presence of ketoconazole in the seminal plasma, although the measured concentrations of ketoconazole were no more than one tenth that needed for in vitro activity. The serum levels of testosterone in the dogs receiving oral ketoconazole were profoundly suppressed but the extreme rapidity of onset of the ex vivo effect on sperm motility, which was noted within 4 hours of dosing, makes it unlikely that testosterone withdrawal plays more than a minor role in the spermatostasis. The results in animals invite further pursuit of this novel, rapid onset, reversible, single dose use of spermatostatic agents for their potential as male contraceptives.