Folic acid metabolism in Rauscher murine leukemia and effect of methotrexate on the blood picture

Folic acid contents of plasma, whole blood, liver and spleen in Rauscher leukemic mice were estimated. Plasma and liver folate in the leukemic mice was lower than that of normal mice, suggesting that folic acid was deficient in Rauscher leukemia. Folic acid contents in whole blood and spleen were even higher in the leukemic mice than those in normal mice. Clearance study by injecting folic acid intravenously into leukemic mice showed faster disappearance of folic acid from the circulating blood, suggesting that folic acid demand of Rauscher leukemia is increased. Methotrexate administered shortly after inoculation of the virus did not prevent Rauscher leukemia. But anemia, reticulocytosis and erythroblastosis, which are commonly seen 3-4 weeks later in leukemic controls, were not marked as compared with controls. It can be concluded that the requirement of folic acid is greater in Rauscher leukemia than in controls, and methotrexate is effective for preventing hematological changes commonly seen in this type of leukemias.