title: Anti-luteinizing (LH)-releasing activity of several analogues of LH-releasing hormone.
abstract: The anti-LH-releasing activity of several analogues of LH-RH was tested by 2-hour infusion in ovariectomized, estrogen-progesterone-pretreated rats and in immature male rats. [Leu3]LH-RH, [Leu3, desGly10]-LH-RH ethylamide, [desHis2, Leu3,desGly10]-LH-RH ethylamide, [Gly2, Leu3,desGly10]-LH-RH ethylamide, [Leu1, desGly10]-LH-RH ethylamides, [desHis2,D-Ala6,desGly10]-LH-RH ethylamide, [desHis2,Leu3,D-Ala6, desGly10]-LH-RH ethylamide, and [D-pGlu1,desGly10]-LH-RH ethylamide, and and [D-pGlu1,desHis2,desGly10]-LH-RH ethylamide showed some anti-LH-releasing activity, but never completely inhibited the increase in serum LH in response to LH-RH. No significant differences were found among the analogues tested and [desHis2,desGly10]-LH-RH ethylamide, and inhibitory potency was not improved with those peptides containing D-alanine in position 6 of the chain. None of the analogues tested, including [desHis2,desGly10]-LH-RH ethylamide, was able to block the LH-RH-induced FSH release in these systems.
mesh_terms: D000818:Animals; D005640:Follicle Stimulating Hormone / Q000097:blood; D007987:Gonadotropin-Releasing Hormone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D010455:Peptides / Q000494:pharmacology; D051381:Rats
chemical_list: D010455:Peptides; D007987:Gonadotropin-Releasing Hormone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone