Effect of past and current dietary Zn intake on Zn absorption and endogenous excretion in the rat

Journal Article · Sat Oct 01 00:00:00 EDT 1988 · J. Nutr.; (United States)

OSTI ID:6864762

Johnson, P E; Hunt, J R; Ralston, N V

Effects of previous dietary Zn (or body Zn stores) and current dietary Zn intake on absorption and endogenous excretion of Zn were studied by using radioisotope dilution. Rats were fed diets containing 1.5, 12.6 or 50.3 mg Zn/kg for 19 d (dietary period I). Total body Zn in the three groups was 1870 +/- 340, 3953 +/- 698 and 4126 +/- 844 micrograms Zn/rat. Each group was divided into four subgroups fed 3.6, 12.6, 20.5 or 50.3 mg Zn/kg diet for 3 wk (dietary period II). Rats were injected intramuscularly with 65Zn after 7 d of dietary period II. True absorption and endogenous excretion were calculated by isotope dilution. Zinc intake, urinary and fecal excretion, balance and percent Zn absorption were significantly affected only by dietary Zn in dietary period II (P less than 0.01). Endogenous excretion was affected by both past dietary Zn deficiency (body Zn stores) and by dietary Zn in dietary period II (P = 0.0001). Total body Zn at the end of the experiment was significantly affected by both periods of dietary treatment (P less than 0.001), but total body Zn concentration was affected only by the final dietary treatment (P less than 0.05). These results show that Zn absorption is affected by the current diet, but that turnover of Zn (endogenous excretion) is regulated by both current Zn intake and past Zn intake, probably through an effect on body Zn stores.

• Research Organization: Department of Agriculture, Grand Forks, ND (USA)
• OSTI ID: 6864762
• Journal Information: J. Nutr.; (United States), Journal Name: J. Nutr.; (United States) Vol. 118:10; ISSN JONUA
• Country of Publication: United States
• Language: English

Related Subjects

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560300* -- Chemicals Metabolism & Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ABSORPTION
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BIOLOGICAL WASTES
DAYS LIVING RADIOISOTOPES
DIET
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTS
EVEN-ODD NUCLEI
FECES
INTERMEDIATE MASS NUCLEI
INTESTINAL ABSORPTION
ISOTOPE APPLICATIONS
ISOTOPE DILUTION
ISOTOPES
MAMMALS
MATERIALS
METABOLISM
METALS
NUCLEI
NUTRITIONAL DEFICIENCY
RADIOISOTOPES
RATS
RODENTS
TRACER TECHNIQUES
UPTAKE
VERTEBRATES
WASTES
ZINC
ZINC 65
ZINC ISOTOPES