Nutritional Factors in Hemodynainics

AN INTERRELATIONSHIP between certain of the actions of ascorbic acid and of pteroylglutamic acid (PGA) has been reported recently by several laboratories. The "tyrosyluria" present in vitamin C deficient guinea pigs' can be abolished by the parenteral administration of pteroylglutamic acid, although the deficiency of vitamin C and the subsequent development of scurvy is not ameliorated.2-4 Massive doses of this vitamin will similarly inhibit the anticipated "tyrosyluria" of scorbutic infants.' In addition, young monkeys on a synthetic diet devoid of pteroylglutamic acid and of ascorbic acid develop a megaloblastic anemia which responds either to pteroylglutamic acid or to ascorbic acid administration.6 It has been established previously that vitamin C has an important role in maintaining vasocompensatory processes in the peripheral circulation.7' 8 The evidence outlined briefly above suggested that metabolic association of ascorbic acid and pteroylglutamic acid might conceivably extend into hemodynamic mechanisms. For this reason, studies have been initiated concerning blood pressure levels, tissue vitamin C concentrations and certain peripheral vascular reactions in animals fed synthetic diets with and without pteroylglutamic acid