Ascorbic Acid Therapy of Pteroylglutamic Acid-Deficient Rats

Abstract
A pteroylglutamic acid (PGA)-deficiency syndrome was produced in rats with a synthetic diet containing 2% sulfathalidine or sulfa-suxidine. Growth ceased after 5 wks., and several animals died after 7 weeks. All dead rats and many survivors showed hemorrhagic areas, chiefly around the mouth and nose, and on the paws. The survivers were then fed 2 mg./day of ascorbic acid. Two died in the 2d week, and 1 in the 3d, but none showed hemorrhagic signs. The rest began to gain wt., the white cell count returned to normal, and the formation of nucleated red blood cells became significant. The Hb content and total red cell count decreased and the % of reticulocytes became normal. After 3 wks. on ascorbic acid, 6 of the rats were given orally 50 microg. of PGA/day; a marked reticulocyte response, but no significant increase in number of nucleated red cells occurred. The data confirm the known role of PGA in red blood cell maturation and Hb formation.