title: Growth hormone treatment increases cytochrome P450-mediated antipyrine clearance in man.
abstract: We used the antipyrine clearance test (APC) to examine the effect of growth hormone (GH) therapy on hepatic cytochrome P450 (CYP) enzyme activity. Eleven GH deficient adults were randomized to receive GH or placebo for 6 months, all subjects subsequently received GH. Before treatment, APC was below the normal range in six subjects. We found an increase in APC in the subjects randomized to receive GH compared to those on placebo (median change +0.14 ml/min/kg [range + 0.04 to + 0.20]vs -0.04 ml/min/kg [range -0.07 to + 0.04], p = 0.011). The stimulatory effect of GH on drug metabolism was confirmed by the data for 3 months GH treatment in all 11 subjects, with APC increasing from 0.33 ml/min/kg (range 0.22 to 0.69) to 0.50 ml/min/kg (range 0.27 to 0.83), p = 0.018). These data indicate that GH modulates hepatic CYP activity. This has important clinical implications, as the hepatic metabolism of drugs and hormones may be altered in patients undergoing GH therapy.
authors.affiliation: Department of Diabetes and Endocrinology, University of Sydney at Westmead Hospital, NSW, Australia.
authors.forename: N W
authors.initials: NW
authors.lastname: Cheung
authors.forename: C
authors.initials: C
authors.lastname: Liddle
authors.forename: S
authors.initials: S
authors.lastname: Coverdale
authors.forename: J C
authors.initials: JC
authors.lastname: Lou
authors.forename: S C
authors.initials: SC
authors.lastname: Boyages
mesh_terms: D000328:Adult; D000983:Antipyrine; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D004311:Double-Blind Method; D013006:Growth Hormone / Q000009:adverse effects* / Q000172:deficiency* / Q000627:therapeutic use; D006801:Humans; D008657:Metabolic Clearance Rate; D010919:Placebos; D011994:Recombinant Proteins / Q000009:adverse effects; D012016:Reference Values
chemical_list: D010919:Placebos; D011994:Recombinant Proteins; D013006:Growth Hormone; D003577:Cytochrome P-450 Enzyme System; D000983:Antipyrine