A study of LH-RH receptors in the pituitary gland of the winter flounder (Pseudopleuronectes americanus Walbaum).
A study using an iodinated [D-Ser(tBu)6,Pro9-NHEt]LH-RH (Buserelin), demonstrated the presence of a single class of high-affinity (KD = 2.90 nM), high-capacity LH-RH binding sites in pituitaries obtained from sexually mature male and female winter flounder. Displacement curves for unlabeled Buserelin and other preparations of mammalian and fish LH-RH, but a lack of competition for structurally unrelated peptide hormones, indicated the hormone specific nature of the fish pituitary LH-RH receptor preparation. Compared with native mammalian LH-RH and salmon LH-RH, Buserelin and an analog of salmon LH-RH, [D-Arg6,Trp7,Leu8,Pro9-NHEt]LH-RH, had significantly higher binding affinities for the flounder pituitary receptor correlating with results of previous studies demonstrating the superagonist biological activity of LH-RH analogs in trout and goldfish.
Crim
L W
LW
Marine Sciences Research Laboratory, Memorial University of Newfoundland, St. John's, Canada.
St Arnaud
R
R
Lavoie
M
M
Labrie
F
F
D000818:Animals; D001667:Binding, Competitive; D002064:Buserelin / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D005260:Female; D005412:Flatfishes / Q000378:metabolism*; D005432:Flounder / Q000378:metabolism*; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives / Q000378:metabolism; D008297:Male; D010902:Pituitary Gland / Q000378:metabolism*; D011966:Receptors, LHRH / Q000378:metabolism*
D011966:Receptors, LHRH; D007987:Gonadotropin-Releasing Hormone; D002064:Buserelin