Studies on the Biochemical Defect of Pernicious Anemia. I. In Vitro Observations on Oxygen Consumption, Heme Synthesis and Deoxyribonucleic Acid Synthesis by Pernicious Anemia Bone Marrow12

In microbiological systems, folic acid and vita- min B12 appear to be important in the synthesis of purines and pyrimidines, in the synthesis of methyl groups, and possibly in the synthesis of deoxyribose (1-3).Studies at the clinical level, summarized by Mueller and Will (4), indicate that similar biochemical processes may be involved in patients with pernicious anemia (P.A.). Be- cause such studies on patients are difficult to carry out and interpret, precise methods of in vitro as- sessment of the biochemical activity of P. A. mar- row cells are needed.Direct studies on P. A. marrow have been con- fined, for the most part, to observations of morphologic changes and cell counts in tissue culture(5-12).In attempting to avoid the difficulties inherent in evaluating these changes in tissue cul- ture and in an effort to secure more direct biochemical information, P. A. marrow has been studied in our laboratory by the following techniques: 1) oxygen consumption, 2) heme synthesis as measured by the rate of incorporation of C14- glycine into heme, and 3) deoxyribonucleic acid (DNA) synthesis by measurement of the rate of incorporation of C14-formate into thymine.With these techniques, which permit measure- ments of biochemical activity over short periods of time and with small amounts of bone marrow, we have attempted to answer the following ques- tions: 1) Does vitamin B12 have a direct effect on P. A. marrow cells?2) Why has the liquid cul- ture-vaccine vial technique failed to demonstrate an