title: Absorption and conversion of a single oral dose of beta-carotene in corn oil to vitamin A in Sprague-Dawley rats with low reserve of vitamin A.
abstract: This study was carried out to determine how much of a single oral dose of beta-carotene in oil is absorbed and how much of the absorbed dose is converted to retinoids in rats having a vitamin A reserve at the lowest end of adequate status. Weanling rats raised on a vitamin A-deficient diet for four weeks were given a single oral dose of either corn oil or beta-carotene dissolved in corn oil (1.86 mumol). Serum, liver, and the entire digestive tract of the rats were analyzed for carotenoids and retinoids. Results showed that 4 hours after dosing, 1.64 mumol (88%) of the dose of beta-carotene was found intact, with 17.6% found in the stomach, 21% in the small intestine, and 49.3% in the large intestine. A total of 0.28 mumol of newly formed retinoids (expressed as retinyl palmitate) was present in serum, liver, and mucosa of small intestine. The results suggest that a single oral dose of beta-carotene might not be an effective way of raising vitamin A status in rats.
authors.affiliation: Department of Biochemistry, Biophysics & Molecular Biology, Iowa State University, Ames, IA 50011, USA. abarna@iastate.edu
authors.forename: Arun B
authors.initials: AB
authors.lastname: Barua
mesh_terms: D000284:Administration, Oral; D000818:Animals; D002338:Carotenoids / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D003314:Corn Oil / Q000008:administration & dosage*; D041981:Gastrointestinal Tract / Q000378:metabolism; D007408:Intestinal Absorption / Q000502:physiology; D008099:Liver / Q000378:metabolism; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012176:Retinoids / Q000378:metabolism; D014801:Vitamin A / Q000096:biosynthesis*; D014802:Vitamin A Deficiency / Q000378:metabolism*; D019207:beta Carotene / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics*
chemical_list: D012176:Retinoids; D019207:beta Carotene; D014801:Vitamin A; D002338:Carotenoids; D003314:Corn Oil