384 ON URIC ACID FORMATION 



nucleins, from the decomposition products the nuclein bases 

 of which uric acid seems to arise, at least in the mam- 

 malia."* Hammarsten writes : " An increase in the quantity 

 of uric acid eliminated has been observed by many investiga- 

 tors in lineal leucaemia, while the reverse has been observed 

 under the influence of quinine in large doses, which produces 

 an enlargement of the spleen. We have here a rather posi- 

 tive proof that there is a close relationship between the spleen 

 and the formation of uric acid." Again, " a direct relationship 

 between the spleen and the formation of uric acid in man, has 

 been sought by several investigators. According to the inves- 

 tigations of Horbaczewski this relationship seems to be of an 

 indirect kind, as it probably stands in close connection with the 

 importance of the spleen to the formation of the leucocytes." f 

 These statements, to which those of other writers $ might 

 be added, are for the most part due to the influence which 

 the well-known investigations of Horbaczewski have exerted. 

 This investigator observed that when spleen pulp is exposed 

 to incipient putrefaction, considerable quantities of xanthin 

 and hypoxanthin can be isolated from the mixture. If, how- 

 ever, the pulp at this stage is subjected to conditions which 

 facilitate oxidation, e.g., shaking with air in the presence of 

 blood, xanthin bases are no longer obtained, but uric acid is 

 found in place of them. These observations have repeatedly 

 been verified. Spitzer, in particular, has studied the con- 

 ditions under which this mode of formation of uric acid may 

 be facilitated. His investigations lead to the conclusion that 

 extracts of both spleen and liver, as well as the tissue pulp, 

 may yield uric acid when subjected to a current of air for 



Neumeister, Lehrbuch der physiologischen Chemie. 1897, p. 512. 



t Hammarsten, Textbook of Physiological Chemistry, translated by Man- 

 del, 1900, pp. 200, 431. 



t E. g., Stadthagen, Archiv fur pathologische Anatomie, 1887, cix, p. 403 ; 

 Bunge, Lehrbuch der physiologischen und pathologischen Chemie, 1894, 

 p. 814; Howell, American Textbook of Physiology, 1896, p. 273; Simon, 

 Manual of Clinical Diagnosis, 1897, p. 349 ; Schreiber, Ueber die Harnsaure 

 unter physiologischen und pathologischen Bedingungen, Stuttgart, 1899, p. 90. 



Spitzer, Archiv f iir die gesammte Physiologic, 1899, Ixxvi, p. 192. 



