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The inadequacy of urinary Nτ-methyl histidine excretion in the pig as a measure of muscle protein breakdown

Published online by Cambridge University Press:  09 March 2007

C. I. Harris  and
G. Milne
C. I. Harris
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen, AB2 9SB
G. Milne
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen, AB2 9SB
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Abstract

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1. The validity of the urinary excretion of Nτ-methyl histidine (Nτ-MH) by pigs as an index of muscle protein breakdown in vivo was tested using the criterion of the rate of recovery of radioactivity in urine following an intravenous dose of Nτ-[14CH3]methyl histidine.

2. Urinary recoveries of radioactivity from five animals were less than 21% of dose in 7 d after which the daily recovery was less than 0.3% per day.

3. The incomplete recoveries of radioactivity were associated with the presence in muscle of a large. pool of non-protein-bound Nτ-MH, the concentration of which increased with age.

4. The Nτ-MH in this pool was present as free Nτ-MH and in a dipeptide which constituted more than 90% of the total non-protein-bound Nτ-MH. The contribution of the peptide increased with age, reaching 99.8% in older animals.

5. The pool of non-protein-bound Nτ-MH was maintained and increased in both established and newly accreted tissue by retention of some of the Nτ-MH released by muscle protein breakdown, only a proportion of which was therefore available for excretion. Hence, the urinary excretion of Nτ-MH is not a valid index of muscle protein breakdown in pig.

Type
Papers on General Nutrition
Information
British Journal of Nutrition , Volume 45 , Issue 2 , March 1981 , pp. 423 - 429
Copyright
Copyright © The Nutrition Society 1981

References

REFERENCES

Badger, T. M. & Tumbleson, M. E. (1974). J. Nutr. 104, 1339.CrossRefGoogle Scholar
Crush, K. G. (1970). Comp. Biochem. Physiol. 34, 3.CrossRefGoogle Scholar
Delaporte, C., Mean, G. & Broyer, M. (1978). Am. J. clin. Nutr. 31, 1647.CrossRefGoogle Scholar
Garlick, P. J., Burk, T. L. & Swick, R. W. (1976). Am. J. Physiol. 230, 1108.CrossRefGoogle Scholar
Hams, C. I. & Milne, G. (1977). Proc. Nutr. Soc. 36, 138A.Google Scholar
Hams, C. I. & Milne, G. (1979). Proc. Nutr. Soc. 38, 11A.Google Scholar
Hams, C. I. & Milne, G. (1980). Br. J. Nutr. 44, 129.Google Scholar
Hams, C. I. & Milne, G. (1980). Biochem. Soc. Trans. 8, 552.Google Scholar
Hams, C. I. & Milne, G. (1981). Br. J. Nutr. 45, 411.Google Scholar
Hams, C. I., Milne, G., Lobley, G. E. & Nicholas, G. A. (1977). Biochem. Soc. Trans. 5, 706.Google Scholar
Long, C. L., Haverberg, L. N., Young, V. R., Kenney, J. M., Munro, H. N. & Geiger, J. W. (1975). Metabolism 24, 929.CrossRefGoogle ScholarPubMed
Milne, G. & Hams, C. I. (1978). Proc. Nutr. Soc. 37, 18A.Google Scholar
Rangley, W. R. D. & Lawrie, R. A. (1976). J. Fd Technol. 11, 143.CrossRefGoogle Scholar
Young, V. R., Alexis, S. C., Baliga, B. S., Munro, H. N. & Muecke, W. (1972). J. biol. Chem. 247, 3592.CrossRefGoogle Scholar
Young, V. R. & Munro, H. N. (1978). Fedn Proc. Fedn Am. Socs exp. Biol. 37, 77.Google Scholar