title: Increases in Serum Growth Hormone Concentrations Associated with GHB Administration.
abstract: The administration of gamma-hydroxybutyrate (GHB) has been reported to augment the increase in growth hormone (GH) secretion associated with the onset of sleep. The ability of GHB to stimulate GH production in the absence of sleep in both male and female volunteers was investigated as part of a GHB administration study. Twelve healthy volunteers (six men and six women) were given a small oral dose (25 mg/kg) of GHB (as Xyrem®) at 10:00 h. Basal blood samples (as serum) were taken 10 min prior to GHB administration, with additional samples taken at 10, 15, 20, 25, 30, 45, 60, 90, 120, 150, 180, 240, 360 and 480 min post-administration. The serum concentrations of GHB were measured by GC-MS and GH by immunometric assay. Following GHB administration, volunteers exhibited effects consistent with mild sedation, i.e., relaxed with normal responses to verbal stimuli. Despite none being asleep, an increase in serum GH concentration occurred in 11 out of the 12 volunteers (5 women and 6 men). In these volunteers, peak GH concentrations occurred 45-60 min post-administration compared with a mean serum tmaxfor GHB of 23 min (SD = 5.4 min). The absolute increase in GH was similar for men and women, averaging 3.4 and 3.7 ng/mL, respectively. The mean intra-individual increase in GH was much greater in males (29 times) compared with females (2 times), as males had (as expected) smaller basal GH concentrations (mean = 0.26 ng/mL) compared with females (mean = 5.4 ng/mL). After maximizing, the GH concentration decreased rapidly (in agreement with GHB concentrations), returning to basal concentrations at ~90-120 min post-administration. GHB administration at a small therapeutic dose results in increases in serum GH concentrations in healthy male and female volunteers in the absence of sleep onset.
authors.affiliation: Department of Pharmacy and Forensic Science, Analytical and Environmental Sciences, King's Forensics, Drug Control Centre, 150 Stamford Street, King's College London, London SE1 9NH, UK alan.brailsford@kcl.ac.uk.
authors.forename: Alan D
authors.initials: AD
authors.lastname: Brailsford
authors.affiliation: Department of Pharmacy and Forensic Science, Analytical and Environmental Sciences, King's Forensics, Drug Control Centre, 150 Stamford Street, King's College London, London SE1 9NH, UK.
authors.forename: Christiaan
authors.initials: C
authors.lastname: Bartlett
authors.affiliation: Department of Pharmacy and Forensic Science, Analytical and Environmental Sciences, King's Forensics, Drug Control Centre, 150 Stamford Street, King's College London, London SE1 9NH, UK.
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Kicman
authors.affiliation: Department of Pharmacy and Forensic Science, Analytical and Environmental Sciences, King's Forensics, Drug Control Centre, 150 Stamford Street, King's College London, London SE1 9NH, UK.
authors.forename: David A
authors.initials: DA
authors.lastname: Cowan
mesh_terms: D000284:Administration, Oral; D000328:Adult; D015992:Body Mass Index; D004305:Dose-Response Relationship, Drug; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D013006:Growth Hormone / Q000097:blood*; D006801:Humans; D008297:Male; D012890:Sleep; D012978:Sodium Oxybate / Q000008:administration & dosage* / Q000097:blood; D055815:Young Adult
chemical_list: D012978:Sodium Oxybate; D013006:Growth Hormone