Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-25T02:24:58.205Z Has data issue: false hasContentIssue false
  • English
  • Français

The Catabolism of valine in the malnourished rat. Studies in vivio and in vitro with different labelled forms of valine

Published online by Cambridge University Press:  07 January 2011

P. J. Reeds
P. J. Reeds
Affiliation:
Tropical Metabolism Research Unit, University of the West Indies, Mona, Kingston 7, Jamaica
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

1. The catabolism of valine was estimated in vivo by measurement of the production of labelled CO2 for 2 h after the oral administration of either [U-14C]valine or [I-14C] valine. It was also estimated in vitro in homogenates of liver and muscle incubated with labelled valine. Experiments were performed in rats given diets providing either 215 g (HP) or 25 g (LP) protein per kg diet.

2. The proportion of [U-14C]-valine excreted as 14CO2 was not reduced in rats given the LP diet for 16 d but the excretion of 14CO2 from [I-14C]valine was reduced by 40% in these animals. When rats were transferred from the HP diet to the LP diet there was a reduction in the excretion of 14CO2 from [I-14C]valine; when the diet was changed from LP to HP output of 14CO2 increased to control values.

3. Homogenates of muscle and liver catabolized valine to CO2. Both liver and muscle from rats fed on the LP diet catabolized less [I-14C]valine than tissues from control animals.

4. Valine aminotransferase activity was higher in muscle than in liver, and did not change in tissues from rats fed on the LP diet. In these animals 2-ketoisovaleric acid dehydrogenase activity was reduced in both liver and muscle.

5. The production of 14CO2 was lower with [U-14C]valine as the substrate than with [I-14C]valine and there was no difference between tissues from rats fed on the HP and LP diets.

6. The results with [I-14C]valine suggest that both liver and muscle from protein-depleted rats catabolize valine at a reduced rate. The reason for the discrepancy between these results and those with [U-14C]valine is not clear. It is concluded that the results with [U-14C]valine in vitro are affected by dilution of the label before the formation of 14CO2, but that this does not hold in vivo.

Type
General Nutrition
Information
British Journal of Nutrition , Volume 31 , Issue 2 , March 1974 , pp. 259 - 270
Copyright
Copyright © The Nutrition Society 1974

References

REFERENCES

Aquilar, T. S., Harper, A. E. & Benevenga, N. J. (1972). J. Nutr. 102, 1199.CrossRefGoogle Scholar
Arroyave, G., Wilson, D., de Funes, G. & Béhar, M. (1962). Am. J. clin. Nutr. 11, 517.CrossRefGoogle Scholar
Chan, H. (1968). Br. J. Nutr. 22, 315.CrossRefGoogle Scholar
Das, T. K. & James, W. P. T. (1972). Int. Congr. Nutr. IX, Mexico City, Abstr. p. 4.Google Scholar
Diem, K. (editor) (1971). Documenta Geigy Scientific Tables 6th ed. Manchester: Documenta Geigy.Google Scholar
Flores, H., Sierralta, W. & Mockeberg, F. (1970). J. Nutr. 100, 375.CrossRefGoogle Scholar
Grimble, R. F. & Whitehead, R. G. (1971). Br. J. Nutr. 25, 253.CrossRefGoogle Scholar
Health, D. F. & Threlfall, C. J. (1968). Biochem. J. 110, 337.CrossRefGoogle Scholar
Kim, J. H. & Miller, L. L. (1969). J. biol. Chem. 244, 1410.CrossRefGoogle Scholar
LaNoue, K. F., Nicklas, W. J. & Williamson, J. R. (1970). J. biol. Chem. 245, 102.CrossRefGoogle Scholar
Lowry, O. H., Rosenbrough, N. J., Farr, A. R. & Randall, R. J. (1951). J. biol. Chem. 193, 265.CrossRefGoogle Scholar
McFarlane, I. G. & von Holt, C. (1969 a). Biochem. J. 111, 567.Google Scholar
McFarlane, I. G. & von Holt, C. (1969 b). Biochem. J. 111, 565.CrossRefGoogle Scholar
Manchester, K. L. (1965). Biochim. biophys. Acta 100, 295.CrossRefGoogle Scholar
Meister, A. (1965). Biochemistry of the Amino Acids 2nd ed. Vol. 2, p. 730. New York: Academic Press.Google Scholar
Miller, L. L. (1962). In Amino Acid Pools p. 708 [ Holden, J. T., editor]. Amsterdam: Elsevier.Google Scholar
Millward, D. J. (1970). Clin. Sci. 39, 577.CrossRefGoogle Scholar
Mimura, T., Yamada, C. & Swenseid, M. E. (1968). J. Nutr. 95, 493.CrossRefGoogle Scholar
Mortimore, G. E. & Mondon, C. E. (1970). J. biol. Chem. 245, 2375.CrossRefGoogle Scholar
Neale, R. J. (1971). Nature, New Biol. 231, 117.CrossRefGoogle Scholar
Neale, R. J. (1972). Biochim. biophys. Acta 273, 80.CrossRefGoogle Scholar
Neale, R. J. & Waterlow, J. C. (1974). Br. J. Nutr. (In the Press.)Google Scholar
Odessey, R. & Goldberg, A. L. (1972). Am. J. Physiol. 223, 1376.CrossRefGoogle Scholar
Pain, V. M. & Manchester, K. L. (1970). Biochem. J. 118, 209.CrossRefGoogle Scholar
Schimke, R. T. (1962). J. biol. Chem. 237, 1921.CrossRefGoogle Scholar
Sketcher, R. D., Fern, E. B. & James, W. P. T. (1974). Br. J. Nutr. (In the Press.)Google Scholar
Steele, R., Altzuler, N., Wall, J. S.Dunn, A. & de Bodo, R. C. (1959). Am. J. Physiol. 196, 221.CrossRefGoogle Scholar
Stephen, J. M. L. & Waterlow, J. C. (1968). Lancet i, 118.CrossRefGoogle Scholar
Wolhueter, R. M. & Harper, A. E. (1970). J. biol. Chem. 245, 2391.CrossRefGoogle Scholar
Yamashita, K. & Ashida, K. (1969). J. Nutr. 99, 267.CrossRefGoogle Scholar