Experimental Biology and Medicine · 1954 · 12 citations · 0 references
PharmacyPharmacokineticsPharmacologyBioavailabilityMineral MetabolismRenal PharmacokineticsMicronutrient AbsorptionMicronutrient BioavailabilityVitamin B12 PhysiologyVitamin BiochemistryVitamin ChemistryVitamin PhysiologyBioavailability Of Vitamin B12Dietary Vitamin B12 BioavailabilityGastrointestinal Absorption Of CobalaminHepatic Vitamin B12 HandlingRadioactivity MeasurementVitamin B12 (Cobalamin)Vitamin B12 ClearanceVitamin B12 Metabolism
1. The effect of a clinically active intrinsic factor concentrate on the absorption of cobalt 60 labeled vit. B12 by rats after oral administration has been studied. 2. Measurements of the radioactivity of kidneys, livers and urine indicate lowered absorption in the presence of intrinsic factor concentrate. Fecal radioactivity is too variable to permit reliable conclusions. 3. Injection of a massive dose (20 μg) of normal B12 4 days after oral administration of the labeled vitamin liberates additional urinary radioactivity, and again points to an inhibitory effect of intrinsic factor concentrate.