title: Beta-carotene, retinol and retinyl ester concentrations in serum and selected tissues of ferrets fed beta-carotene.
abstract: The concentrations of beta-carotene, retinol and retinyl esters in serum and selected tissues of ferrets fed diets supplemented with beta-carotene (80 micrograms/g wet diet) for 3 wk were determined. The initial concentration of serum beta-carotene was 0.011 +/- 0.006 mumol/L (mean +/- SEM); at the end of the experimental period it was 5.75 +/- 1.60 mumol/L. No significant differences in serum retinol and total retinyl esters were observed between beta-carotene-fed and control ferrets that had been fed an unsupplemented diet. The predominant retinyl esters in serum were retinyl stearate (53%) and retinyl palmitate (35%). Of the tissues analyzed after beta-carotene feeding, the liver contained the highest concentration of beta-carotene (78.8 +/- 18.8 nmol/g). Other tissues that contained beta-carotene in amounts ranging from 17 to 20 nmol/g were adrenals, small intestine, stomach and colon; lesser amounts (6.9 nmol/g) were found in kidneys. Amounts ranging from 1.2 to 2.3 nmol/g were found in muscle, bladder, adipose tissue, lungs and skin; only 0.37 and 0.34 nmol/g were present in brain and eyes, respectively. Thus, like humans, ferrets have the capacity to absorb intact beta-carotene and to store this compound in tissues, especially the liver. However, compared with humans, ferrets have elevated concentrations of retinyl esters in serum, liver and other tissues.
authors.affiliation: U.S. Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, MA 02111.
authors.forename: J D
authors.initials: JD
authors.lastname: Ribaya-Mercado
authors.forename: J G
authors.initials: JG
authors.lastname: Fox
authors.forename: W D
authors.initials: WD
authors.lastname: Rosenblad
authors.forename: M C
authors.initials: MC
authors.lastname: Blanco
authors.forename: R M
authors.initials: RM
authors.lastname: Russell
mesh_terms: D000042:Absorption; D000311:Adrenal Glands / Q000378:metabolism; D000818:Animals; D002338:Carotenoids / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D004032:Diet; D004224:Diterpenes; D005289:Ferrets / Q000378:metabolism*; D005753:Gastric Mucosa / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D009928:Organ Specificity; D000084562:Retinyl Esters; D014801:Vitamin A / Q000031:analogs & derivatives / Q000097:blood / Q000378:metabolism*; D019207:beta Carotene
chemical_list: D004224:Diterpenes; D000084562:Retinyl Esters; D019207:beta Carotene; D014801:Vitamin A; C014794:retinol palmitate; D002338:Carotenoids; C042811:retinyl stearate