抄録
Attempts were made to develop a metabolic model for human megaloblastic anemia due to cobalamin (vitamin B12) or folate deficiency using a cell culture system. When cultured in the folate-and B12-deprived medium supplemented with CH3-THF at 10 ng/ml or 250 ng/ml, the L1210 cells were rendered folate-deficient 48 hours after transfer. This was evidenced by retarded growth, decreased DNA synthesis and marked improvement of deoxyuridine (UdR) incorporation following either folic acid or CH3-THF addition, whereas B12 did not significantly affect these parameters. However, pretreatment of the medium with nitrous oxide resulted in the development of B12-deficient state, as indicated by improved UdR incorporation following B12 addition. The results also indicated that, at least in this culture system, a concomitant folate-deficiency was a prerequisite for the development of overt B12-deficiency by nitrous oxide exposure. This model system may be useful as an experimental tool for further elucidation of the biochemical mechanisms of megaloblastic anemia.
