Glucose promotes whole-body protein synthesis from infused aminoacids in fasting man. Isotopic demonstration.
15N-glycine constant infusion, with plateau urea enrichment as the endpoint, demonstrated a clear increase in whole-body protein synthesis when glucose was added to aminoacid infusion in fasting men. Whole-body protein-breakdown rates remained unchanged. There was an unexpected fall in whole-body nitrogen turnover when the subjects were changed from an oral intake to either of the intravenous programmes: this finding, not previously reported, may be due to the decrease in gastrointestinal enzyme synthesis and intestinal-lining cell-turnover when oral intake is replaced by total parenteral nutrition.
D000284:Administration, Oral; D001835:Body Weight; D004032:Diet; D004038:Diet, Reducing; D004040:Dietary Carbohydrates / Q000008:administration & dosage / Q000378:metabolism; D002149:Energy Intake; D005215:Fasting; D005947:Glucose / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D005998:Glycine / Q000008:administration & dosage*; D006801:Humans; D007263:Infusions, Parenteral; D007553:Isotope Labeling; D008297:Male; D009124:Muscle Proteins / Q000096:biosynthesis; D009584:Nitrogen / Q000378:metabolism; D009587:Nitrogen Isotopes; D014176:Protein Biosynthesis
D004040:Dietary Carbohydrates; D009124:Muscle Proteins; D009587:Nitrogen Isotopes; D005947:Glucose; D009584:Nitrogen; D005998:Glycine