[The effect of the external biliary diversion on cobalamin functions].

We studied the effect of the external biliary diversion on cobalamin functions clinically and experimentally. Serum cobalamin was rising to 10 ng/ml or more in each patient with obstructive jaundice and the diverted bile contained high concentrations of cobalamin (10-80 ng/ml). A total volume of diverted cobalamin reached to 2-12 micrograms/day after the relief of obstruction and was maintained 2-8 micrograms/day even after 30 days. In experimental dogs, serum cobalamin decreased to 360 +/- 40pg/ml (about 31% decreases) subsequent eight weeks after the relief. The cobalamin concentration of liver decreased to 184 +/- 123ng/g (19% decreases) after four weeks and to 164 +/- 108ng/g (30% decreases) after eight weeks. The concentration of the different cobalamins in the liver showed that the proportion of dimethyl benzimidazolyl cobamide coenzyme (DBCC) decreased and the proportion of methylcobalamin increased. It is concluded that cobalamin (10 micrograms/day at least) should be administered when the diversion continues for a long term.