Biliary Excretion of Co60 Labeled Vitamin B12 in Dogs.

Abstract

Cobalt60 labeled vitamin B12 was injected intravenously into dogs and the biliary excretion of C06O followed. The excretion pattern has 2 components. The fast component half-time varies from 6.0 to 7.5 hours. The slow component varies from 90 to 295 hours. It is clear that biliary excretion does not account for total fecal excretion in dogs. Further investigation is needed to determine whether the compartments represented by the 2 components are parallel with different turnover rates or in series and mutually dependent. The anatomical or biochemical nature of the compartments, remains obscure.