SPLEEN. 371 



guanase and adenase (LEVENE, SCHITTENHELM, JONES and PARTRIDGE, 

 JONES and WINTERNITZ), by the first of which the guanine is transformed 

 into xanthine, and by the latter the adenine into hypoxanthine. The 

 guanase also occurs in the spleen of the ox and horse, but not ( JONES), 

 or only in small amounts (SCHITTENHELM), in the pig-spleen. 1 The 

 spleen also contains two enzymes, lienases, as shown by HEDIN (and 

 ROWLAND), one of which, the a-lienase, acts chiefly in alkaline solution, 

 while the other, 6-lienase, is active only in acid reaction. These enzymes, 

 which without doubt stand in close relation to the leucocytes, not only 

 act autolytically upon the proteins of the spleen, but they also dissolve 

 fibrin and coagulated blood-serum. The spleen also contains nucleases 

 and besides, as TANAKA 2 has found for the pig-spleen, diastase, invertin, 

 lipase, urease, trypsin and an erepsin like enzyme. 



Among the constituents of the spleen the deposit rich in iron, which 

 consists of ferruginous granules or conglomerate masses of them, and 

 which is derived from a transformation of the red blood-corpuscles, is of 

 special interest. It was closely studied by NASSE. This deposit does 

 not occur to the same extent in the spleen of all animals. It is found 

 especially abundant in the spleen of the horse. NASSE 3 on analyzing 

 the grains (from the spleen of a horse) obtained 840-630 p. m. organic 

 and 160-370 p. m. inorganic substances. These last consisted of 566- 

 726 p. m. Fe 2 3 , 205-388 p. m. P 2 O 5 , and 57 p. m. earths. The organic 

 substances consisted chiefly of proteins (660-800 p. m.), nuclein (52 p. m. 

 maximum), a yellow coloring-matter, extractive bodies, fat, cholesterin, 

 and lecithin. 



In regard to the mineral constituents, it is to be observed that the 

 amount of iron in new-born and young animals is small (LAPICQUE, 

 KRUGER, and PERNOU), in adults more appreciable, and in old animals 

 sometimes very considerable. NASSE found nearly 50 p. m. iron in the 

 dried pulp of the spleen of an old horse. GUILLEMONAT and LAPICQUE 4 

 have determined the iron in man. They find no regular increase with 

 growth, but in most cases 0.17-0.39 p. m. (after subtracting the blood- 

 iron) calculated on the fresh substance. A remarkably high amount of 

 iron is not dependent upon old age, but is a residue from chronic diseases. 

 MAGNUS-LEVY found 0.72 p. m. iron in the fresh human spleen. 



x See Chapter XIV for the literature. 



2 Hedin and Rowland, Zeitschr. f. physiol. Chem., 32, and Hedin, Journ. of Physiol., 

 30, and Hammarsten's Festschr., 1906; Tanaka, Bioch. Zeitschr, 37. 



3 Maly's Jahresber., 19, p. 315. 



4 Lapicque, ibid., 20; Lapicque and Guillemonat, Compt, rend, de soc. biol., 48. 

 and Arch de Physiol. (5) 8; Kriiger and Pernou, Zeitschr. f. Biologic, 27; Nasse, cited 

 from Hoppe-Seyler, Physiol. Chem., 720. 



