Plasma Vitamin A Homeostasis: The Relative Dose Response As A Measure Of Liver Vitamin A Reserves

Retinol levels in plasma of rats are constant and independent of dietary intake or liver stores above 10 μg per gram. If tissue needs of retinol are decreased by limiting protein intake or by feeding retinoic acid, plasma levels correspondingly decline. A single dose of newly supplied vitamin A leads to a short-term surge in plasma retinol level which may be a measure of liver reserves and vitamin A status.