GROWTH-HORMONE AFTER ABDOMINAL-SURGERY ATTENUATED FOREARM GLUTAMINE, ALANINE, 3-METHYLHISTIDINE, AND TOTAL AMINO-ACID EFFLUX IN PATIENTS RECEIVING TOTAL PARENTERAL-NUTRITION

Objective The study clarified the effects of growth.hormone treatment on forearm amino acid efflux in patients with full nutritional support after gastrointestinal surgery. Summary Background Data Growth hormone attenuates net nitrogen loss after surgical trauma. An increase in net protein synthesis has been described, whereas the results regarding protein breakdown have been conflicting. Methods Elective patients undergoing abdominal surgery were double blindly randomized to treatment with recombinant human growth hormone (GH, n = 9) 24 IU or placebo (PL, n = 10) the first 5 postoperative days. All received parenteral nutrition (nitrogen = 5.7 +/- .1 g/mw, energy = 1018 +/- 12 kcal/M2 (125 +/- .7% of BMR) and epidural analgesia. Amino acid plasma levels and forearm fluxes were measured. Results The second postoperative day, growth hormone abolished forearm efflux of total amino acid nitrogen (GH: 170 +/- 117, PL: -785 +/- 192 nmol/100 mL/min, p = .0007) due to reduced losses of both essential and nonessential amino acids. Glutamine release was abolished (13 +/- 15 vs. -137 +/- 43 nmol/100 mL/min, p = .007) and alanine release attenuated (-61 +/- 17 vs. -211 +/- 51 nmol/100 mL/min, p = .01). 3-Methyl-histidine release was attenuated (-.20 +/- .11 vs. -.62 +/- .09 nmol/100 mL/min, p = .04). Growth hormone also induced decreased venous plasma amino acid levels. Conclusions When given after gastrointestinal surgery in patients treated with total parenteral nutrition, growth hormone treatment abolished glutamine, 3-methylhistidine, and total amino acid nitrogen loss from forearm tissue. Alanine loss from forearm tissue was attenuated.