title: Recombinant human growth hormone improves muscle amino acid uptake and whole-body protein metabolism in chronic hemodialysis patients.
abstract: BACKGROUND
  Intradialytic parenteral nutrition (IDPN), with or without exercise, has been shown to reverse the net negative whole-body and forearm muscle protein balances observed during hemodialysis. Pharmacologic doses of recombinant human growth hormone (rhGH) constitute another potential anabolic therapy in chronic hemodialysis patients.
  
  
  OBJECTIVE
  Our goal was to examine the potential additive anabolic effects of rhGH compared with IDPN and exercise on protein and energy homeostasis.
  
  
  METHODS
  We studied 7 chronic hemodialysis patients in a crossover design study in which each subject participated in 2 protocols: GH (rhGH + IDPN + exercise) and no GH (IDPN + exercise). During the GH protocol, the subjects were studied after 3 daily doses of rhGH. Each subject was studied 2 h before, 4 h during, and 2 h after a hemodialysis session with the use of a primed, constant infusion of l-[1-(13)C]leucine.
  
  
  RESULTS
  Whole-body net protein balance was -0.50 +/- 0.07 mg x kg fat-free mass(-1) x min(-1) when the patients did not receive rhGH and -0.39 +/- 0.04 mg x kg fat-free mass(-1) x min(-1) when the patients received rhGH, a 22% improvement in prehemodialysis whole-body protein homeostasis (P < 0.05). Essential amino acid muscle loss was also significantly less during the prehemodialysis period when rhGH was administered (-18 +/- 23 compared with -71 +/- 20 mmol/L; P < 0.05). The whole-body anabolic effects of rhGH observed during the prehemodialysis period persisted throughout the entire study, as evidenced by a lack of significant interaction or main effect of treatment during hemodialysis and in the posthemodialysis period.
  
  
  CONCLUSIONS
  rhGH improves whole-body protein homeostasis in chronic hemodialysis patients.
authors.affiliation: Department of Medicine, Division of Nephrology, Vanderbilt University Medical Center, Nashville, TN 37232-2372, USA.
authors.forename: Lara B
authors.initials: LB
authors.lastname: Pupim
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Flakoll
authors.forename: Chang
authors.initials: C
authors.lastname: Yu
authors.forename: T Alp
authors.initials: TA
authors.lastname: Ikizler
mesh_terms: D000328:Adult; D000596:Amino Acids / Q000097:blood / Q000378:metabolism*; D002247:Carbon Isotopes; D018592:Cross-Over Studies; D004734:Energy Metabolism / Q000187:drug effects / Q000502:physiology; D015444:Exercise / Q000502:physiology; D005260:Female; D019382:Human Growth Hormone / Q000494:pharmacology*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000378:metabolism / Q000628:therapy; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism*; D010084:Oxidation-Reduction; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology; D010288:Parenteral Nutrition; D011506:Proteins / Q000378:metabolism*; D011994:Recombinant Proteins / Q000494:pharmacology*; D006435:Renal Dialysis / Q000009:adverse effects; D016896:Treatment Outcome
chemical_list: D000596:Amino Acids; D002247:Carbon Isotopes; D011506:Proteins; D011994:Recombinant Proteins; D019382:Human Growth Hormone