Effect of oral estramustine phosphate on pituitary, gonadal, and adrenal function in the green monkey (Cercopithecus...

We studied the effects of estramustine phosphate on pituitary, gonadal, and adrenal function in the green monkey. A 2-week course of estramustine phosphate (75 mg per day) reversibly suppressed the luteinizing hormone and testosterone response to luteinizing hormone-releasing hormone but did not affect pituitary-adrenal function assessed by the 11-deoxycorticosterone response to metyrapone. Treatment with oral estramustine phosphate also resulted in a significant increase in corticosteroid-binding globulin but did not affect a series of liver enzymes nor hematology. The results are consistent with a pure estrogen effect produced by hydrolysis of the carbamate-ester bona at a site distant from estrogen target tissues and could explain most of the reported in vivo effects of this compound.