292 A CHEMICO-PHYSIOLOGICAL STUDY OF 



Influence on blood coagulation. The older literature on the 

 influence of so-called " peptone " on blood coagulation is too 

 familiar to physiologists to require detailed consideration here. 

 Briefly stated, the researches* made have demonstrated (a) 

 that "peptone" does not of itself possess any clot-preventing 

 power, t. ., the action is an indirect one; and (6) that 

 accordingly the clot-preventing power must be attributed to 

 some substance formed within the organism and possessing 

 a peculiar influence on the blood. Furthermore, it seems 

 probable that the peculiar substance is not a transformation 

 product of the "peptone" itself, but is rather a result of 

 other changes taking place in the body.f More recently, 

 through the researches of Contejean,J Gley, and Pachon, and 

 especially through the researches of Delezenne,|| the seat of 

 formation of the anti-coagulating substance has been dele- 

 gated to the liver, and the important r6le which the leucocytes 

 play in this action has been demonstrated by Delezenne 

 (1898). The explanation formulated at present is as follows: 

 It has long been known that the intravenous injection of 

 " peptone " leads to a pronounced disintegration of leucocytes. 

 Delezenne assumes that this process is accompanied by the 

 liberation of two classes of products, the one accelerating and 

 the other inhibiting blood coagulation. As types of such 

 bodies, the researches of Lilienfeld If and others have indicated 

 nucleoproteids, which give rise to intra vascular clotting, and 

 histon, a peculiar peptone-like body occurring in leucocytes in 

 the compound nucleo-histon. When these two classes of com- 

 pounds (clot-retarding and clot-accelerating substances) are 



* Schmidt-Mulheim, Archiv f. Physiol. 1880, p. 30; Fano, Ibid., 1881, 

 p. 277 ; Pollitzer, Journal of Physiology, 1886, vii, p. 283 ; Campbell, Studies 

 from the Biological Laboratory, Johns Hopkins University, 1887, iv, p. 1; 

 Grosjean, Archives de biologie, 1892, xii ; Ledoux, Ibid., 1896, xiv, p. 63. 



t Cf. Campbell, loc. cit. 



t Contejean, Archives de physiologic, 1895. 



Gley and others, Ibid. It is to be noted, however, that Starling (Journal 

 of Physiology, 1896, xix, p. 15) has not been able to confirm part of these 

 experiments. 



|| Delezenne, Archives de physiologie, 1897, p. 646 ; 1898, p. 508. 



f Lilienfeld, Zeitschr. f . physiol. Chem. 1895, xx, p. 89. 



