Hematologic Effect of 5,6-dimethyl-benzimidazolyl Cobamide Coenzyme in a Patient with Pernicious Anemia.

Since 5, 6-dimethylbenzimidazolyl cobamide coenzyme (coenzyme B12) as one of the coenzyme forms of vitamin B12 was reported by Barker et al. (1) for the first time in 1960, a good deal of works have been carried out on its biochemical and physiological roles (2-8). The recent knowledge concerning the coenzyme has revealed that it is an active form of vitamin B12 (5, 6-dimethylbenzimidazolyl cobamide cyanide, CN-B12), which has been applied to the clinical use for 15 years, and that CN-B12 itself does not participate in the enzymatic reactions unless converted into the coenzyme form (1, 10), although its intestinal absorption mechanism is almost similar to that of the cyanide form in terms of intrinsic factor dependency (4--8). It would be reason able that these observations have led us to the idea that the parent oral administration of coenzyme B12 must be one of the most effective way to treat the perniciosa patient and that it is worth-while trying to investigate the clinical effectiveness of coenzyme B12.