Evidence for an Hypothalamic Focus of Inhibition of Gonadotropin by Androgen in the Male. ∗

Abstract

Summary

The chronic implantation of minute amounts of solid testosterone propionate into the posterior median eminenceposterior tuberal region of the hypothalamus in 4 dogs has led to aspermia and profound testicular and prostatic atrophy. Although decreases in quality of semen were noted in 2 of 4 other dogs with similar implants in the pituitary, none of these 4 dogs showed gonadal or prostatic atrophy. No decrease in semen quality nor gonadal or prostatic atrophy was noted in either of 2 dogs with thalamic implants or one with an implant in the ventromedial hypothalamus.

The authors would like to thank Enid Arozena, Cora Rucker and Arlene Koithan for skilled technical assistance.