title: Structure-activity relationships of mammalian, chicken, and salmon gonadotropin releasing hormones in vivo in goldfish.
abstract: Mammalian, chicken, and salmon gonadotropin releasing hormones (GnRHs), and anlogs of each peptide, were injected either alone or in combination with pimozide into goldfish, and the changes in serum gonadotropin (GtH) levels determined. The native peptides had similar potencies in terms of magnitude and duration of the GtH response. Analogs of LHRH that are superactive in mammals are also superactive in goldfish; although [(imBzl)-D-His6, Pro9-NEt]-LHRH is very highly superactive in mammals it has activity similar to [D-Ala6, Pro9-NEt]-LHRH in goldfish. D-Ala6 or (imBzl)-D-His6 substitutions of [Trp7, Leu8, Pro9-NEt]-LHRH are not superactive in goldfish, whereas the D-Arg6 substitution is highly superactive, indicating that there are differences in the factors that make salmon and mammalian GnRH superactive. These results also indicate that the structural modifications that determine superactivity of GnRHs in goldfish differ from what is known for mammals.
mesh_terms: D000818:Animals; D002645:Chickens; D003530:Cyprinidae / Q000097:blood*; D004357:Drug Synergism; D005260:Female; D006054:Goldfish / Q000097:blood*; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives / Q000494:pharmacology*; D006062:Gonadotropins / Q000097:blood*; D008297:Male; D010868:Pimozide / Q000494:pharmacology; D010906:Pituitary Hormone-Releasing Hormones / Q000494:pharmacology*; D012474:Salmon; D013329:Structure-Activity Relationship
chemical_list: D006062:Gonadotropins; D010906:Pituitary Hormone-Releasing Hormones; D010868:Pimozide; D007987:Gonadotropin-Releasing Hormone