QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Weigand, E. Articles by Kirchgessner, M. Search for Related Content PubMed PubMed Citation Articles by Weigand, E. Articles by Kirchgessner, M.

Total True Efficiency of Zinc Utilization: Determination and Homeostatic Dependence upon the Zinc Supply Status in Young Rats

Institut fuer Ernaehrungsphysiologie der Technischen Universitaet Muenchen, D-8050 Freising-Weihenstephan, Federal Republic of Germany

Total true efficiency of zinc utilization and its component factors, true absorption and metabolic efficiency, were studied in relation to dietary zinc supply in a 15-day experiment with 36 weanling rats in six groups. After day 3, the initial supply of 18.2 ppm zinc in the diet for all groups was changed to 5.6, 10.6, 18.2, 39, 70 and 141 ppm in groups 1 to 6, respectively. During the 6-day balance period after day 9, zinc intake was proportional to dietary zinc concentration. Mean daily rates of weight gain and apparent zinc retention increased from a near zero level in group 1 to a high plateau from group 4 to 6. True absorption rate steadily rose and reached about twice that of apparent absorption in group 6. This difference in rates was due to endogenous zinc excretion. Percent total utilization and percent true absorption steadily declined from a mean of about 100 in groups 1 and 2 to nearly 15 and 30, respectively, in group 6. Metabolic efficiency, reflecting true retention of absorbed zinc, similarly declined as percent true absorption did. The major conclusion was that not only the absorptive but also the metabolic efficiency greatly contributed to zinc homeostasis and total true efficiency of zinc utilization.

KEY WORDS: • zinc homeostasis • total utilization • true absorption • metabolic efficiency • endogenous excretion • rats

Manuscript received 4 June 1979.

This article has been cited by other articles:

				J. R Hunt, J. M Beiseigel, and L. K Johnson Adaptation in human zinc absorption as influenced by dietary zinc and bioavailability Am. J. Clinical Nutrition, May 1, 2008; 87(5): 1336 - 1345. [Abstract] [Full Text] [PDF]