Temporal changes in FSH and LH concentrations following the administration of a potent LH-RH inhibitory analogue ( [N-Ac-D-Trp1, 3, D-p-Cl-Phe2, D-Phe6, D-Ala10]-LH-RH) to oophorectomized rhesus monkeys.
A series of studies was performed in order to assess the antigonadotropic potency of an inhibitory analogue of LH-RH (IA-LH-RH) ( [N-Ac-D-Trp1, 3, D-p-Cl-Phe2, D-Phe6, D-Ala10]-LH-RH) in oophorectomized rhesus monkeys. I) Single administration of 1 mg IA-LH-RH im resulted in a prompt and significant decrease of serum levels of FSH and LH which lasted for at least 24 h. A specific rebound of serum LH to higher concentrations than baseline occurred in all animals at +48 or +72 h. II) Exogenous LH-RH at a dose of 150 micrograms was administered iv 2 or 18 h after the injection of 1 mg IA-LH-RH. Blood was drawn at 0, 10, 20, 30, 60, 120 and 180 min post LH-RH. The rise in LH and FSH levels observed in the control animals was not altered when LH-RH was administered 2 h after the antagonist, but it was significantly inhibited and delayed when LH-RH was given 18 h after the LH-RH inhibitory analogue. These results show that antagonistic analogues of LH-RH are potent inhibitors of gonadotropin concentrations in non-human primates. Their potential use in conditions in which inhibition of gonadotropin secretion and/or release is desired is discussed.
D000818:Animals; D002369:Castration; D002940:Circadian Rhythm / Q000187:drug effects; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood*; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D007986:Luteinizing Hormone / Q000097:blood*; D008253:Macaca mulatta; D010060:Ovulation / Q000187:drug effects
D007987:Gonadotropin-Releasing Hormone; C039243:LHRH,(N)-Ac-Trp(1)-(4-Cl-Phe)(2)-Trp(3)-Phe(6)-AlaNH2(10)-; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone