j^-AMINOBENZOIC ACID 



effect when given to patients infected with rickettsiae ^ (see page 

 557). It was therefore tried out in the treatment of patients with 

 chronic lymphatic leukemia and chronic myeloid leukemia. It 

 caused a profound fall in the leucocyte count when administered in 

 doses of 50 g. a day. The haemoglobin content of the blood was 

 reduced slightly.^ The division of myeloid cells appeared to be 

 stimulated at low concentrations and depressed at high concentrations. 



References to Section 6 



1. B. F. Sieve, Science, 1941, 94, 257. 



2. H. Brandalcone, E. Main and J. M. Steele, Proc. Soc. Exp. Biol. 



Med., 1943, 53, 47. 



3. J. J. EUer and L. A. Diaz, N.Y. Sta. J. Med., 1943, 43, 1331. 



4. S. Rothman and J. Rabin, /. Invest. Dermat., 1942, 6, 445. 



5. A. Yeomans, J. C. Snyder, E. S. Murray, C. J. D. Zarafonetis and 



R. S. Ecke, /. Amer. Med. Assoc, 1944, 126, 349 ; P. K. Smith, 

 ihid., 1946, 131, 1114 ; N. A. Tierney, ibid., 280. 



6. H. B. May and J. Vallence-Owen, Lancet, 1948, 2, 607. 



7. 2VIETABOLISM OF p-AMINOBENZOIC ACID 



_^-Aminobenzoic acid is excreted in human urine, probably in con- 

 jugated form, and in human faeces (see pages 77, J^).'^ By using 

 _^-aminobenzoic acid containing N^^, Lustig et al.^ demonstrated that 

 the substance was neither stored nor utilised by mice. 



The average concentration of _/)-aminobenzoic acid in human sweat 

 was 0-24 /xg. per 100 ml.^ 



There is convincing evidence that ^-aminobenzoic acid is synthes- 

 ised by the intestinal flora of humans, for Denko et al.^ found that 

 the faecal excretion greatly exceeded the dietary intake. It is not 

 known whether the _/)-aminobenzoic acid so formed is absorbed. 



Administration of _/)-aminobenzoic acid to guinea-pigs resulted in 

 a decrease of the bacterial population of the intestine and in the total 

 disappearance of the Gram-negative lactose-fermenting bacilli.* 



References to Section 7 



1. E. Strauss, F. C. Lowell and M. Finland, /. Clin. Invest., 1941, 20, 



189 ; C. W. Denko, W. E. Grundy, J. W. Porter, G. H. Berryman, 

 T. E. Friedemann and J. B. Youmans, Arch. Biochem., 1946, 10, 

 33 ; C. W. Denko, W. E. Grundy, N. C. Wheeler, C. R. Hender- 

 son, G. H. Berryman, F. E. Friedemann and J. B. Youmans, 

 ibid., 1946, 11, 109. 



2. B. Lustig, A. R. Goldfarb and B. Gerstl, Arch. Biochem., 1944, 5, 59. 



3. B. C. Johnson, H. H. Mitchell and T. S. Hamilton, /. Biol. Chem., 



1945. 161. 357- 



4. D. M. Whitney and L. Anigstein, /. Bact., 1946, 52, 400. 



554 



