ADENIN. 349 



white blood corpuscles, which owing to various unfavorable condi- 

 tions, become destroyed in time, and the contained nuclein, as a re- 

 sult, splits up into adenin and guanin. These two bases may, there- 

 fore, be expected in all pathological conditions where there is an 

 abnormal accumulation of pus. Indeed, as early as 1865, Naunyn 

 extracted from pus, obtained from the pleural cavity, a considerable 

 quantity of a substance which was probably either adenin or guanin, 

 or both. Neither uric acid nor xanthin bases in recognizable 

 amounts are present in fresh human blood (100-300 c.c.) ; both are 

 present in exudates and transudates (Jaksch). In the blood of leu- 

 ksemics and in blood after a diet of thymus glands uric acid is pres- 

 ent in increased quantity (Petren). 



Adenin does not occur, or only in minute traces, in meat extract ; 

 and in this it resembles guanin, which is present only in traces. 

 This may be due to the fact that adenin and guanin are readily con- 

 verted into hypoxanthin and xanthin respectively, as has been shown 

 in the putrefaction experiments of Schindler. This conversion of 

 adenin and guanin into hypoxanthin and xanthin takes place in the 

 pancreas immediately after death, so that the amount of adenin found 

 may be quite small. They may be considered as transitional products 

 of cell metabolism, the amido group contained in each readily being 

 replaced by oxygen, and giving rise to ammonia, and this in turn to 

 urea. Kossel, however, explained this fact on the ground that the 

 muscle tissue is very poor in nucleated cells, i. e., in nuclein. It 

 would seem that the muscle cell in losing the morphological char- 

 acter of a cell has also suffered a corresponding loss in its chemical 

 properties. For while the decomposition products of nuclein — hy- 

 poxanthin, xanthin, phosphoric acid, etc. — are found in the muscle 

 tissue, they do not exist in combination as they do in the nuclein 

 molecules. This is seen in the fact that the bases exist in the free 

 condition, since they can be extracted by water ; and again, the phos- 

 phoric acid is present in the muscle tissue, not in organic combina- 

 tion, but as a salt. In the nucleated cell, adenin, guanin, etc., do 

 not exist in a free condition, but form, in part at least, with albu- 

 min and phosphoric acid, a loose combination which is readily de- 

 composed by the action of acids at the boiling temperature. This 

 same change takes place spontaneously after death. It is quite pos- 

 sible that the existence of these bases in muscles, in the free condi- 

 tion, is due to the action of enzymes. 



There can be no doubt that adenin and guanin play an important 

 part in the physiological function of the cell nucleus, which, from 

 recent observations, appears to be necessary to the formation and 

 building up of organic matter. It is now known that non-nucleated 

 cells, though capable of living, are not capable of reproduction. We 

 must look, therefore, to the nucleus as the seat of the functional 

 activity of the cell — indeed, of the entire organism. Nuclein, the 



