EFFECT OF DEFICIENCY IN ANIMALS 



Pteroylglutamic acid did not affect the anaemia that resulted 

 when rats on a purified diet were given thiourea, but it did correct 

 the granulocytopenia that occasionally accompanied the anaemia and 

 which was regularly produced when, in addition to thiourea, thyroid 

 powder or thyroxine was given. ^^ Pantothenic acid-deficient rats 

 sometimes develop granulocytopenia or anaemia or both and, in this 

 instance also, pteroylglutamic acid relieved the granulocytopenia 

 (when alone), but not the anaemia.^^ The anaemia, when alone, was 

 relieved by pantothenic acid. When both granulocytopenia and 

 anaemia occurred together, both pantothenic acid and folic acid 

 were required. Feeding protein-free or low-casein diets to rats also 

 resulted in granulocytopenia and anaemia.^^ To rectifj^ the granulo- 

 cytopenia in this instance both casein and pteroylglutamic acid were 

 necessary. 



Synthetic pteroylglutamic acid at a level of no fig. per day in- 

 creased the body^veight and the leucocyte count of lactating rats, 

 but no further increase was obtained by giving larger amounts. '^^ 

 Larger amounts (275 [ig. per day) were necessary in order to effect a 

 significant improvement in the weaning weights of the yoimg, but 

 doubling this amount did not bring about any further improvement. 

 Pteroylglutamic acid has a beneficial effect on both lactation and 

 reproduction, and rats fed on a diet containing succinylsulphathiazole 

 and deficient only in pteroylglutamic acid for i to 3 months before 

 breeding showed impaired reproduction,*^ whilst the addition of 0-5 % 

 of an antagonist resulted in 100 % resorptions, even without prior 

 deficiency.** 



Crystalline pteroylheptaglutamate increased the total leucocytes 

 and granulocytes in sulphasuxidine-treated rats, as effectively as did 

 pteroylglutamic acid when given orally and only slightly less effectively 

 when injected ; the presence of an inhibitor of vitamin B© conjugase 

 did not affect the utilisation of the conjugate.*^ 



Mice 



Folic acid is also essential for mice and according to E. Nielsen and 

 A. Black *® the deficiency symptoms were rendered more acute when 

 0-6 % of sulphasuxidine was added to the diet. Franklin et al.,^'' 

 however, failed to produce symptoms of pteroylglutamic acid de- 

 ficiency in mice by giving sulphasuxidine. One of the symptoms 

 apparently characteristic of folic acid deficiency in mice is poor lacta- 

 tion performance ; this was considerably improved by the adminis- 

 tration of folic acid concentrates and of the pure factor.*^ 



Pteroylglutamic acid-deficient mice also show a reduction in 

 the counts of all the cellular elements of the circulating blood and 



489 



