514 THE BIOCHEMISTRY OF B VITAMINS 



inclusion of succinylsulfathiazole further decreases hepatic storage of 

 these vitamins. 280 Administration of folic acid and biotin returns the 

 hepatic storage of these vitamins to normal. A marked decrease in hepatic 

 storage of pantothenic acid which occurs on administration of succinyl- 

 sulfathiazole is not corrected by administration of large amounts of 

 pantothenic acid, whether administered orally or parenterally ; however, 

 supplements of folic acid and biotin allow normal storage of pantothenic 

 acid in the liver, besides alleviating the symptoms normally attributed 

 to pantothenic acid deficiency. 280 



Rats on stock diets containing succinylsulfathiazole are normal with 

 respect to hepatic vitamin storage, with the exception of folic acid. The 

 amount of folic acid in the liver is significantly decreased, but is still 

 many times that found in deficient animals. 281 



Succinylsulfathiazole accentuates the folic acid deficiency induced by 

 strain of lactation in rats. The leucopenia and granulocytopenia produced 

 under these conditions are especially severe. 282 



The leukopenia, granulocytopenia and anemia produced in rats by 

 sulfanilamide, sulfathiazole and sulfadiazine are prevented by either folic 

 acid or p-aminobenzoic acid. 283 



Sulfapyridine fed at a level of 1 per cent of the diet produces symptoms 

 of pantothenic acid deficiency, i.e., roughening of the fur, coproporphyrin 

 deposits on the noses, wrists and whiskers, hemorrhagic necrosis of the 

 adrenal glands, retardation of growth, and in black rats achromotrichia. 

 All these symptoms except retardation of growth are relieved by rela- 

 tively large supplements of pantothenic acid. 284 - 285 The ability of panto- 

 thenic acid to counteract these effects is in contrast to the deficiency 

 obtained with succinylsulfathiazole. 



Xanthopterin has been reported to alleviate the leukopenia of rats fed 

 a purified diet containing succinylsulfathiazole. 285a However, several at- 

 tempts to confirm this effect were not successful. 278 - 279, 286 > 287 More re- 

 cently, xanthopterin has been reported to produce an immediate response 

 in alleviating the anemia in rats fed a synthetic diet containing 1 per 

 cent sulfathiazole. 28S Folic acid was effective only after a delay of three 

 to five days. 288 Subsequent results indicated that the optimal dose of 

 xanthopterin was 1 mg per kg of body weight and that 10 mg not only 

 was ineffective but intensified the anemia. 289 Similar results were obtained 

 with xanthopterin and folic acid in stimulating cell proliferation of iso- 

 lated bone marrow. 290 



Ascorbic acid is reported to be effective in treatment of the leucopenia 

 occurring in rats fed a purified diet containing either succinylsulfathiazole 

 or phthalylsulfathiazole. 291 



Sulfonamides are reported to have a delayed carcinogenic action, 

 though less than that of dibenzanthracene in albino rats and mice. 292 



