High Cholesterol Content of Human Spleen 15 



material with a phosphorus content of 1 • 9 per cent and a 

 nitrogen content of 2 • 97 per cent. The ether-soluble fraction 

 represented 25 • 6 per cent of the dry weight. There followed an 

 extraction with warm methanol and chloroform. This procedure 

 yielded 44-4 g. of lipids, or 20-7 per cent of the dry weight. 



The lipids resulting from the ether extraction were separated 

 in the usual way and showed the following composition: fats 

 and unsaponifiable matter, 25-6 g.; phospholipids, 21-0 g.; 

 protagon, 8-3 g. The fats and unsaponifiable matter 

 together amounted to 11-9 per cent of the dry residue. The 

 iodine number was 93 • 0, the acid index 34 • 4 and the saponi- 

 fication value 58-3. By shaking the ethereal solution with 

 alkali we obtained 1-32 g. of free fatty acids, and by saponi- 

 fication 19-8 g. (=9-6 per cent) of cholesterol and 2-58 g. of 

 fatty acids from neutral fat. The cholesterol after crystalliza- 

 tion had a melting point of 148°. The estimation of deuterium 

 in this material showed • 04 atom per cent D or a D-value 

 of 7. The D-content of the fatty acids was somewhat lower 

 (0-03 per cent). 



The high content of cholesterol in the spleen, amounting 

 to 9 • 6 per cent of the dry residue, is striking. In normal 

 spleens we have found that cholesterol represents, for 

 example, • 84 and 1 • 05 per cent of the dry residue. Other 

 authors have obtained similar results. However, Bloom and 

 Kern (1926) found cholesterol in the spleen of a patient 

 suffering from Xiemann-Pick's disease to be 8-31 per cent of 

 the dry residue. Other values mentioned in the literature 

 for abnormal spleens are, however, much lower (1 to 1-9 per 

 cent). Bloch, Borek and Rittenberg (1946) were able to 

 demonstrate in vitro that tissues- of the spleen of normal 

 rats were not able to form cholesterol from acetate. Our 

 observation, that a few days after giving heavy water the 

 cholesterol present in very high concentration in the diseased 

 spleen already contains deuterium, indicates that under such 

 conditions a synthesis of cholesterol takes place in the spleen. 

 The storage of this steroid would appear to result from an 

 increased synthetic capacity of the diseased organ. 



