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A study of whole-body isotope dilution of [14C]ascorbic acid in guinea-pigs with graded ascorbate intakes

Published online by Cambridge University Press:  09 March 2007

C. J. Bates
Affiliation:
MRC Dunn Nutrition Unit, Downham's Lane, Milton Road, Cambridge CB4 1XJ
Harumi Tsuchiya
Affiliation:
MRC Dunn Nutrition Unit, Downham's Lane, Milton Road, Cambridge CB4 1XJ
P. H. Evans
Affiliation:
MRC Dunn Nutrition Unit, Downham's Lane, Milton Road, Cambridge CB4 1XJ
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Abstract

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The purpose of the present study was first to assess the extent to which unlabelled ascorbate in the diet of guinea-pigs can exchange with labelled ascorbate within their organs when the dietary intake is varied over a wide range, and second to determine whether the retention of label might be used to assess either the amount of ascorbate intake or its biological availability where these are not known. The retention of [14C]ascorbate in the body and in various organs of guinea-pigs were, therefore, measured following a 13 d period of graded dietary intakes of ascorbate. It was found first, that the amount of label retained in each of the organs, 13 d after the initial dose of labelled ascorbate, was much more closely related to the amount of ascorbate intake after labelling than to the intake (and tissue ascorbate levels) before and at the time of labelling. Second, most of the individual internal organs exhibited a constant relationship between the specific activity at 13 d and the dietary intake, except for brain which was flushed to a smaller extent. Third, in agreement with several previous studies a high proportion of the radioactive label in the tissues was found to be still present in ascorbate. The specific activity of column-purified ascorbate was very similar to the estimated specific activity in the crude extract, which implies that it may be possible to estimate specific activities (or stable isotope enrichments) at certain sites without rigorous isolation procedures. Fourth, the amount of radioactivity appearing in the urine 2 d before killing the animals was correlated with the amount of ascorbate intake and with tissue specific activities, suggesting that intakes (or bioavailability) might be predicted from the patterns of label-appearance in the urine

Type
Micronutrient Metabolism and Interactions
Copyright
Copyright © The Nutrition Society 1992

References

Abt, A. F. & von Schuching, S. (1961). Catabolism of L-ascorbic-l-C14 acid as a measure of its utilization in the intact and wounded guinea-pig on scorbutic, maintenance and saturation diets. Annals of the New York Academy of Sciences 92, 148158.CrossRefGoogle ScholarPubMed
Atkins, G. L., Dean, B. M., Griffin, W. J. & Watts, R. W. E. (1964). Quantitative aspects of ascorbic acid metabolism in man. Journal of Biological Chemistry 239, 29752980.CrossRefGoogle ScholarPubMed
Baker, E. M., Hodges, R. E., Hood, J., Sauberlich, H. E. & March, S. C. (1969). Metabolism of ascorbic-1-14C in experimental human scurvy. American Journal of Clinical Nutrition 22, 549558.CrossRefGoogle ScholarPubMed
Bates, C. J. & Cowen, T. D. (1988). Effects of age and dietary vitamin C on the contents of ascorbic acid and acid-soluble thiol in lens and aqueous humour of guinea-pigs. Experimental Eye Research 46, 937945.CrossRefGoogle ScholarPubMed
Bates, C. J., Cowen T. D. & Tsuchiya, H. (1988). Growth, ascorbic acid and iron contents of tissues of young guinea-pigs whose dams received high or low levels of dietary ascorbic acid or Fe during pregnancy and suckling. British Journal of Nutrition 60, 487497.CrossRefGoogle ScholarPubMed
Burns, J. J., Burch, H. B. & King, C. G. (1951). The metabolism of 1-C14-L-ascorbic acid in guinea-pigs. Journal of Biological Chemistry 191, 501514.CrossRefGoogle Scholar
Burns, J. J., Dayton, P. G. & Schulenberg, S. (1956). Further observations on the metabolism of L-ascorbic acid in guinea-pig. Journal of Biological Chemistry 218, 1521.CrossRefGoogle Scholar
Ginter, E., Zloch, Z., Cerven, J., Nemec, R. & Babala, J. (1971). Metabolism of L-ascorbic acid-l-14C in guinea-pigs with alimentary cholesterol atheromatosis. Journal of Nutrition 101, 197204.CrossRefGoogle Scholar
Hornig, D. & Hartmann, D. (1982). Kinetic behaviour of ascorbic acid in guinea pigs. Advances in Chemistry Series 200, pp. 293316. Washington, DC: The American Chemical Society.Google Scholar
Hornig, D., Weber, F. & Wiss, O. (1974). Studies on the distribution of (1-14C) ascorbic acid and (l-14C) dehydroascorbic acid in guinea-pigs after oral application. International Journal of Vitamin and Nutrition Research 44, 217223.Google Scholar
Hornig, D. & Weiser, H. (1976). Interaction of erythorbic acid with ascorbic acid catabolism. International Journal of Vitamin and Nutrition Research 46, 4047.Google ScholarPubMed
Hornig, D., Weiser, H., Weber, F. & Wiss, O. (1973). Effect of massive doses of ascorbic acid on its catabolism in guinea-pigs. International Journal of Vitamin and Nutrition Research 43, 2833.Google ScholarPubMed
Kallner, S., Hartmann, D. & Hornig, D. (1979). Steady state turnover and body pool of ascorbic acid in man. American Journal of Clinical Nutrition 32, 530539.CrossRefGoogle ScholarPubMed
Kipp, D. E. & Rivers, J. M. (1984). Comparison of isotope dilution and excretion methods of determining the half-life of ascorbic acid in the guinea-pig. Journal of Nutrition 114, 13861396.CrossRefGoogle ScholarPubMed
Klain, G. J., Turnbull, J. D. & Omaye, S. T. (1981). Oxidation of 1-14C-ascorbic acid in the guinea-pig: effect of the route of administration. International Journal of Vitamin and Nutrition Research 51, 3946.Google ScholarPubMed
Salomon, L. L. (1957). Ascorbic acid catabolism in guinea-pigs. Journal of Biological Chemistry 228, 163170.CrossRefGoogle ScholarPubMed
Salomon, L. L. (1962). Catabolism of L-ascorbic acid in guinea-pigs. Journal of Nutrition 76, 493502.CrossRefGoogle ScholarPubMed
Tillotson, J. A. (1980). Ascorbate oxidation in the guinea-pig. Nutrition Reports International 22, 555561.Google Scholar
Vuilleumier, J. P. & Keck, E. (1989). Fluorimetric assay of vitamin C in biological materials using a centrifugal analyser with fluorescence attachment. Journal of Micronutrient Analysis 5, 2534.Google Scholar
Zloch, A. & Ginter, E. (1988). Influence of age on the kinetics of vitamin C catabolism in guinea-pigs. Physiologia Bohemoslovaca 37, 459466.Google ScholarPubMed