Assessment of vitamin A status by an isotope dilution method.
The body pool of Vitamin A was estimated by an isotope dilution method and the values obtained were compared with values for total liver Vitamin A obtained by chemical analysis. Rats with varying hepatic levels of Vitamin A were administered a single oral dose of [11,12-3H] retinol at two dose levels (10 micrograms and 20 micrograms) and sacrificed on the seventh day after dosing. The vitamin A body pool was calculated by dividing total liver radioactivity by the specific activity of plasma Vitamin A. At both dose levels significant correlations between analysed and calculated values were obtained at low and high levels of liver Vitamin A, but not at intermediate levels. There was considerable variability in the proportion of the administered dose stored in the liver.
D000818:Animals; D004305:Dose-Response Relationship, Drug; D008099:Liver / Q000378:metabolism*; D008297:Male; D011865:Radioisotope Dilution Technique; D051381:Rats; D014316:Tritium; D014801:Vitamin A / Q000097:blood / Q000378:metabolism*; D014802:Vitamin A Deficiency / Q000378:metabolism
D014316:Tritium; D014801:Vitamin A