Modification of vitamin A metabolism in rats fed a copper-deficient diet.
The liver is the main storage site of vitamin A and copper. Inverse relationships between copper and vitamin A liver concentrations have been suggested. We have investigated the consequences of a copper-deficient diet on liver and blood vitamin A storage in Wistar rats. Animals were fed either a copper-deficient diet for 45 days from weaning, or an identical diet containing adequate amounts of copper. Concentrations of vitamin A were determined by isocratic high performance liquid chromatography using UV detection. We have observed in the liver of the rats fed a copper-deficient diet a significantly higher mean level of retinyl esters (148 +/- 37 micrograms/g of liver) and retinol (3.3 +/- 1.4 micrograms/g of liver) compared to the mean concentration of the retinyl esters (53 +/- 8.5 micrograms/g of liver) (p less than 0.01) and retinol (1.4 +/- 0.5 micrograms/g of liver) (p less than 0.01) in controls. Opposite results were observed in the serum of the group fed a copper-deficient diet as these rats had a significantly lower level of retinol (22 +/- 4 micrograms/100 ml) compared to the mean concentration in the controls (64 +/- 20 micrograms/100 ml) (p less than 0.01). These findings suggest that a copper-deficient diet may cause defective transport of vitamin A from liver to blood. This experimental model may be useful to further investigate unusual liver vitamin A and copper concentrations observed in children during various hepatobiliary diseases.
Rachman
F
F
INSERM U 56, Université Paris-Sud, Hôpital d'Enfants, Bicêtre, France.
Conjat
F
F
Carreau
J P
JP
Bleiberg-Daniel
F
F
Amedee-Manesme
O
O
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003300:Copper / Q000172:deficiency*; D004032:Diet; D008099:Liver / Q000378:metabolism; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D014801:Vitamin A / Q000097:blood / Q000378:metabolism*
D014801:Vitamin A; D003300:Copper