The Clinical and Experimental Studies on the Metabolism of Folic Acid Using Tritiated Folic Acid

Publisher Website
Google Scholar
Abstract
The plasma clearance and urinary excretion of 3H-FA were observed in normal subjects and patients with hematological and hepatic diseases. 3h-FA in a dose of 20 [mu]g/kg of body weight was intravenously injected. The plasma clearance was observed for 6 hrs. and the urinary excretion for 12 hrs. The values are given. An abnormally rapid clearance and low urinary excretion of 3h-FA were observed in all the cases of pernicious anemia and in almost all the cases of aplastic anemia. In some cases of acute leukemia abnormally rapid clearance and low urinary excretion of 3H-FA were observed, while in patients with chronic leukemia all cases showed an abnormally rapid clearance and low urinary excretion. In patients with acute hepatitis, the results varied from case to case. In some cases of liver cirrhosis and chronic hepatitis, abnormally rapid clearance and low urinary excretion of 3H-FA were observed. Organ distribution and urinary excretion of 3h-FA were observed in the rats after intravenous administration of 50 or 200 [mu]g of 3H-FA per kg of body weight. In rats pretreated with CCl4, high urinary excreting and low hepatic uptake of 3H-FA were observed in the earlv stage, while low urinary excretion and high hepatic uptake were observed in the late stage. These results were in good agreement with those of patients with acute hepatitis. In rats pretreated with amethopterin, disturbed FA metabolism was proved by low hepatic and renal uptakes, and high urinary excretion of 3H-FA. The causes of abnormal plasma clearance and urinary excretion of 3H-FA in man and abnormal organ distribution in rats were discussed in each case.