Comparative pharmacokinetics of vitamin A (retinol) in rats and hamsters

The absorption and elimination of all-trans-retinol in the plasma of rats and hamsters were studied after an oral dose of 45 mg/kg body weight. The hamsters exhibited a higher pretreatment mean circulating retinol concentration than rats maintained on an identical diet. The increase in plasma retinol after a single oral dose was much greater in hamsters than rats. The area under the plasma concentration v. time curve was approximately 60% greater for rats than for hamsters. The elimination half-times for rats were much longer than for hamsters. Plasma retinol uptake and disappearance were consistent with a two-compartment open model with first-order absorption.