Physiology. — "On the Causes of the Emigration of Leukocytes" ^) 

 By K. J. Feringa. (Communicated by Prof. H. J. Hamburger.) 



(Communicated at the meeting of February 25, 1922). 



De Haan*) has siiejgested a method by which in a simple manner, 

 without injuring the laboratory animal, large quantities of poly- 

 nuclear leukocytes can repeatedly be obtained. He injected into the 

 abdomen of his animals fluids such as a starch-solution in NaCl 0.9, 

 and other harmless fluids and thereby obtained invariably a homo- 

 geneous emigration of poly nuclear leukocytes. 



My own investigations were performed systematically according 

 to this method, with a number of liquids in order to demonstrate 

 a definite chemical cause for the emigration of the leukocytes. 1 

 experimented on rabbits. 



For shortness sake I will only summarize the results of these 

 experiments. 



Whatever liquids were injected (electrolytes, non-electrolytes, more 

 or less physiological fluids such as Ringer's solution, ultra filtrate 

 of serum, sterile serum, olive-oil or paraffin) the result was invariably 

 an exudation with emigration of many leukocytes. The process of 

 this emigration was the same in all cases. From this 1 concluded 

 that the emigration is not brought on by a specifically chemotactic 

 influence exercised by definite substances upon the leukocytes. 



However, there was still a factor that had been left out of con- 

 sideration, viz. the co7icentration of the hydrogen-ions, which recent 

 inquiries have proved to play a prominent part in diflferent mani- 

 festations of life. 



I considered it rather interesting to ascertain the proceeding of 

 the H-ion concentration in the injected liquid at various intervals 

 after the injection. 



We used for this purpose the colorimetric method and applied 

 phenol-red and cresol-red, recommended by Clark an Lubs*). 



Determinations were made in serum of venous blood and in normal 



Ï) A more detailed communication will appear elsewhere. 



'j J. DE Haan, i.a. Thesis. Groningen 1920. 



») Clark and Lubs, Journ. of bact. 2. 1. 109, 191 (1917). 



