title: Long term effects of administration of a gonadotropin-releasing hormone superagonist analog in men with prostatic carcinoma.
abstract: Administration of the superagonist analog of GnRH, D-Leu6-GnRH proethylamide, profoundly reduced plasma LH, FSH, testosterone, and dihydrotestosterone levels when given for 6-11 weeks to adult men with prostatic carcinoma. Since patients with prostatic carcinoma can be expected to receive this analog for as long as 3-4 yr, we questioned whether the same degree of reduction could be maintained during chronic administration. In 22 men who had received D-Leu6-GnRH proethylamide for at least 1 yr, LH and testosterone remained at the initial low levels. Plasma dihydrotestosterone concentrations, on the other hand, gradually fell further with long term administration. FSH levels reached a nadir of 5.7 +/- 0.94 (+/- SEM) mIU/ml at 10-11 weeks. Unexpectedly, the plasma levels of this gonadotropin then gradually increased, and between 25 and 97 weeks were approximately 10-15 mIU/ml. This pattern occurred identically in patients receiving either 1 or 10 mg D-Leu6-GnRH proethylamide daily. These data indicate persistent suppression of LH and androgen levels during prolonged therapy and suggest that D-Leu6-GnRH-induced "medical castration" can be maintained with chronic administration.
mesh_terms: D000368:Aged; D013196:Dihydrotestosterone / Q000097:blood; D005640:Follicle Stimulating Hormone / Q000097:blood; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000627:therapeutic use; D006801:Humans; D016729:Leuprolide; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000097:blood / Q000188:drug therapy*; D013739:Testosterone / Q000097:blood; D013997:Time Factors
chemical_list: D013196:Dihydrotestosterone; D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D016729:Leuprolide