title: Growth hormone secretagogues: out of competition.
abstract: Growth hormone secretagogues (GHS) constitute a new GH deficiency treatment increasing exponentially in number and improved potency and bioavailability over the last decade. The growth hormone releasing activity makes these compounds attractive for the artificial improvement of the human sports skills, now that recombinant human growth hormone (rhGH) administration is effectively detected. The GHS family is extremely diverse both in number and chemical heterogeneity and keeps growing continuously. In this paper, a general screening test is proposed. To develop a universal method, the single common property of growth hormone secretagogues has been targeted: their capacity to bind to the GHS receptor 1a (GHS-R1a). Pretreated urine samples have been tested in a competition assay where eventually the GHS presence detached a radiolabelled ligand from the receptor in a dose-dependent manner. Blank urine samples were processed to determine potential age, gender and exercise effects, and to define a threshold beyond which a specimen is considered positive. Samples from a growth hormone releasing peptide 2 (GHRP-2) excretion study corroborated the screening assay applicability with a detection window of approximately 4.5 h, and results were confirmed by comparison with a dedicated LC-MS quantification of the intact compound.
authors.affiliation: Bioanalysis Group, Neurosciences Research Program, Municipal Institute for Medical Research-Hospital del Mar, 08003 Barcelona, Spain.
authors.forename: Armand
authors.initials: A
authors.lastname: Pinyot
authors.forename: Zoran
authors.initials: Z
authors.lastname: Nikolovski
authors.forename: Jaume
authors.initials: J
authors.lastname: Bosch
authors.forename: Gerard
authors.initials: G
authors.lastname: Such-Sanmartín
authors.forename: Shinji
authors.initials: S
authors.lastname: Kageyama
authors.forename: Jordi
authors.initials: J
authors.lastname: Segura
authors.forename: Ricardo
authors.initials: R
authors.lastname: Gutiérrez-Gallego
mesh_terms: D000328:Adult; D002853:Chromatography, Liquid / Q000379:methods; D015444:Exercise; D005260:Female; D013007:Growth Hormone-Releasing Hormone / Q000378:metabolism / Q000652:urine*; D006801:Humans; D008297:Male; D013058:Mass Spectrometry / Q000379:methods*; D008875:Middle Aged; D009842:Oligopeptides / Q000378:metabolism / Q000652:urine*; D054440:Receptors, Ghrelin / Q000378:metabolism*; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D009842:Oligopeptides; D054440:Receptors, Ghrelin; D013007:Growth Hormone-Releasing Hormone; C091874:growth hormone-releasing peptide-2