Absorption of vitamin B12 in patients with anaemia after Polya partial gastrectomy

Disorders of cobalamin metabolism

Recent developments in our knowledge of the biochemistry and metabolism of cobalamin have given us some insight into clinical disorders. N2O, which easily induces cobalamin deficiency, both in vivo and in vitro, has greatly contributed to the investigation of the cobalamin deficient state, especially in relation to folate and amino acid metabolism. Demonstration of the cobalamin analog in human serum and a new enzyme which requires cobalamin as a coenzyme has led to recent increased interest in this field. The disorders of cobalamin metabolism will be summarized briefly as well as those areas currently of particular interest.

Vitamin B12 absorption in some neurological and neuroendocrine disorders

An assessment of vitamin B(12) absorption in neurological patients has been made by both serum and urine counting of (57)Co cyanocobalamin during the conventional Schilling test. Although patients with pernicious anaemia, some with subacute combined degeneration of the cord, have been studied, emphasis in the discussion is placed on the significantly increased excretion of the radioactive vitamin in a group of patients with pituitary insufficiency. Results are also given for epileptic patients who have developed folate deficiency (as assessed by serum folate levels) coincidental with anticonvulsant therapy, as well as for some patients who have had neurological symptoms or signs following partial gastrectomy operations.

Comparison of the effects of food and carbachol on the absorption of vitamin B 12 after partial gastrectomy

Absorption of radioactive vitamin B(12) was measured by the Schilling procedure in 14 patients who had had a partial gastrectomy. Injection of carbachol (250 mug) before the administration of the test dose increased absorption to a much smaller degree than the ingestion of a light meal containing a minimal quantity of the natural vitamin. The results support the belief that food may improve absorption of vitamin B(12) after partial gastrectomy by stimulating the secretion of a small residual amount of intrinsic factor.