Uptake of Co⁶⁰-labelled Vitamin B₁₂ in the Fish Tapeworm

Abstract

The fish tapeworm, Diphyllobothrium latum, contains considerable amounts of vitamin B₁₂. Investigations carried out by von Bonsdorff and collaborators have shown:

• 1. that dried fish tapeworm may be used as extrinsic factor in Castle’s test

• 2. that aqueous extracts of the tapeworm parenterally injected bring about maximal haematological remission and improvement of the neurological disturbances in pernicious anaemia

• 3. that an intense vitamin B₁₂-activity is demonstrable in the fish tapeworm with the aid of microbiological methods. For the sake of comparison it may be mentioned that Taenia saginata, which does not seem to be capable of causing pernicious anaemia, contains only 2 per cent of the average amount of vitamin B₁₂ present in Diphyllobothrium latum.