title: Effect of cysteamine hydrochloride on secretion of growth hormone in male swine.
abstract: The objective of this study was to determine the effect of cysteamine hydrochloride (CSH) on growth hormone (GH) secretion in male swine. Twelve Poland China x Yorkshire boars, weighing 103.4 +/- 3.0 kg and fitted with indwelling jugular vein catheters, were individually penned in an environmentally controlled room. Boars received i.v. injections of either 0, 25, 50, or 75 mg CSH/kg body weight (BW) at h 0 (n = 3/treatment). Blood samples were collected every 15 min from h 0 to h 4. Serum concentrations of GH were determined by radioimmunoassay. There was an effect of treatment (P < .05) on mean GH concentrations. Mean GH concentrations (ng/ml) were 1.97 +/- .46, 2.24 +/- .59, .91 +/- .06, and .62 +/- .08 for boars receiving 0, 25, 50, and 75 mg CSH/kg BW, respectively. The dose of CSH-mean GH response had a linear (P < .01) component. Cysteamine hydrochloride at the 75 mg/kg BW dose decreased mean GH concentrations (P < .05) compared to the 0 and 25 mg/kg BW groups. The frequency and amplitude of GH pulses were similar (P > .1) among treatments. Overall, GH pulse amplitude was 2.35 +/- .58 ng/ml and GH pulse frequency was .75 +/- .07 pulses/h. Results from this experiment indicate that CSH suppresses circulating GH concentrations in a dose dependent fashion in boars.
authors.affiliation: Department of Agriculture, University of Maryland Eastern Shore, Princess Anne 21853, USA.
authors.forename: K V
authors.initials: KV
authors.lastname: McElwain
authors.forename: M J
authors.initials: MJ
authors.lastname: Estienne
authors.forename: C R
authors.initials: CR
authors.lastname: Barb
mesh_terms: D000818:Animals; D003543:Cysteamine / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D013006:Growth Hormone / Q000097:blood / Q000378:metabolism*; D007030:Hypothalamo-Hypophyseal System / Q000187:drug effects / Q000502:physiology; D007700:Kinetics; D008297:Male; D013552:Swine / Q000097:blood / Q000502:physiology*
chemical_list: D003543:Cysteamine; D013006:Growth Hormone