Retinol storage in the rat liver after daily intramuscular administration of physiological doses of a vitamin A oil emulsion.
We have recently shown the kinetic behavior of liver retinyl esters in rats with adequate vitamin A levels receiving oral vitamin supplementation. In the present work we have studied the effects of intramuscular administration of a vitamin A preparation on the metabolism of vitamin A in the rat. Retinol administered intramuscularly to rats in the form of an emulsion brought about a significant increase in the serum and liver concentration of vitamin A; this increase was slightly less than in orally treated rats. In each group, retinyl palmitate constituted 80-85% of the total retinyl esters, followed by stearate (9-13%), laurate, palmitoleate, myristate, linoleate and pentadecanoate making up 3-10%. The subcellular localization of all retinyl esters is similar and dependent on age but not on the route of administration. These results indicate that although the best hepatic storage is achieved with an orally administered vitamin A emulsion, the intramuscular administration of a physiological dose might provide an effective supplementation method if oral vitamin A is contraindicated.
Periquet
A
A
INSERM U 87, Institut de Physiologie, Toulouse, France.
Tomatis
I
I
Periquet
B
B
Ghisolfi
J
J
Thouvenot
J P
JP
D000284:Administration, Oral; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004952:Esters / Q000493:pharmacokinetics; D005227:Fatty Acids / Q000032:analysis; D007273:Injections, Intramuscular; D008099:Liver / Q000378:metabolism*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013347:Subcellular Fractions / Q000378:metabolism; D014801:Vitamin A / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*
D004952:Esters; D005227:Fatty Acids; D014801:Vitamin A