Changes in the urinary excretion of acid-soluble peptides in rats injected with streptozotocin or dexamethasone: a trial to estimate the changes in the rate of whole-body protein degradation in those rats
Open Access
- 1 January 1991
- journal article
- Published by Cambridge University Press (CUP) in British Journal of Nutrition
- Vol. 65 (1) , 37-46
- https://doi.org/10.1079/bjn19910064
Abstract
Urinary excretion of acid-soluble peptides (ASP) was measured in rats given streptozotocin or dexamethasone. Streptozotocin-induced diabetic rats excreted increased amounts of urinary nitrogen and ASP-form amino acids. The urinary ratio for N: ASP-form leucine plus valine, which has been shown to reflect the efficiency of dietary N utilization, increased in the diabetic rats, suggesting the impaired utilization of dietary N (and re-utilization of endogenous N). Dexamethasone administration to adrenalectomized rats caused increased excretion of urinary ASP-form leucine plus valine with a concomitant increase in N excretion. However, urinary ratio for N: ASP-form leucine plus valine did not change significantly. The results suggested that dexamethasone caused increased degradation of body proteins, but maintained the efficiency of dietary N utilization or re-utilization of endogenous N. Based on the present observations and the hypothesis proposed previously by the present authors (Noguchi et al. 1988) that urinary excretion of ASP-form leucine plus valine reflects the rate of whole-body protein degradation and the urinary ratio for N: ASP-form leucine plus valine represents N utilization, the origin of urinary N in streptozotocin-diabetic and dexamethasone-administered rats is discussedKeywords
This publication has 12 references indexed in Scilit:
- Further studies on the nutritional factors affecting the urinary excretion of acid-soluble peptides in ratsBritish Journal of Nutrition, 1988
- Modification of glucocorticoid-induced changes in myofibrillar protein turnover in rats by protein and energy deficiency as assessed by urinary excretion ofNT-methylhistidineBritish Journal of Nutrition, 1984
- Time course of the effect of catabolic doses of corticosterone on protein turnover in rat skeletal muscle and liverBiochemical Journal, 1983
- Effect of corticosterone treatment on muscle protein turnover in adrenalectomized rats and diabetic rats maintained on insulinBiochemical Journal, 1982
- The effect of insulin on myofibrillar protein degradation in normal and streptozotocin-induced diabetic rats measured by the rate of N.TAU.-methylhistidine release from perfused hindquarters.Agricultural and Biological Chemistry, 1982
- Some nutritional and physiological factors affecting the urinary excretion of acid soluble peptides in rats and women.Agricultural and Biological Chemistry, 1982
- Effect of glucocorticoid administration on the rate of muscle protein breakdown in vivo in rats, as measured by urinary excretion of Nτ-methylhistidineBiochemical Journal, 1979
- Effect of starvation, refeeding and hydrocortisone administration on turnover of myofibrillar proteins estimated by urinary excretion of N.TAU.-methylhistidine in the rat.Agricultural and Biological Chemistry, 1978
- The relative importance of muscle protein synthesis and breakdown in the regulation of muscle massBiochemical Journal, 1976
- General Aspects of the Regulation of Protein Metabolism by Diet and by HormonesPublished by Elsevier ,1964