Metabolic and endocrine effects of fasting followed by infusion of five-percent glucose
Elwyn, D.H.; Kinney, J.M.; Gump, F.E.; Jeevanandam, M.; Chikenji, T.; Askanazi, J.
Surgery 90(5): 810-816
1981
ISSN/ISBN: 0039-6060 PMID: 7029763 Document Number: 173165
Isotonic glucose is often the only nutrient provided to hospital patients with different degrees of protein-energy malnutrition. To study the effects of such diets uncomplicated by illness, normal persons fasted for 6 to 14 days before receiving an infusion of 5% glucose for 5 to 7 days. Norepinephrine excretion increased steadily to 6 times control values, during the first 6 days of the fast and changed little thereafter. It stayed high during the first 3 days of glucose infusion and subsequently returned toward normal. The rate of N tau -methylhistidine excretion changed little during the fast but decreased abruptly with glucose infusion. The magnitude of N tau -methylhistidine excretion indicated that unidirectional muscle protein degradation was about equal to nitrogen excretion during the fast, and that the decrease in muscle protein degradation could account for the abrupt decrease in N excretion from 91 to 30 mg/kg daily after glucose infusion, and suggests that the conservation of muscle protein caused by glucose infusion in that setting was affected by decreased degradation rather than by increased synthesis. Changes in N tau -methylhistidine excretion and total N excretion were more rapid than, and therefore not mediated by, changes in insulin concentration or norepinephrine excretion.