Physiology. — "Researches on the chemical aivses o I' normal and 

 pathological Haemolysis", \^y R. Brinkman and A.v.Szent- 

 Györgyi. (Communicated by Prof. H. J. Hambiirgb;k). 



(Cominunicatetl at the meetings of February 23 and April 26, 1923). 

 1. Isolation of the haemolytic substances of normal Innnan blood. 



If lias been known for a long time tliat it is possible to isolate 

 fVom normal blood by means of fat-extraction methods groups of 

 substances, wiiidi possess strongly liaemolytic properties. The study 

 of these substances must be important for the explanation of normal and 

 pathological haemolysis, but a definite result revealing their structure 

 ;iii(i manner of action has not yet been ol)tained. NoGCCHi '), when 

 extracting these substances supposed them to be soaps, but he only 

 examined them in regard to immunological phenomena and iiis 

 views were not snpj)orted by later investigators'). Others were 

 thinking of substances with a piiosphatid structure, but could not 

 give sufficiently conclusive proofs'). 



A mor'e exact investigation of the chemical constitution and the 

 physico-chemical form, in which they exist in the blood, is wanted 

 to be able to determine the physio-pathological significance of these 

 substances. We have started from the idea, that it must be desi- 

 rai)le to isolate these substances in a form as pure as possible, to 

 he able to determine their chemical and physico-chemical properties. 

 The (Irst condition to be fulfilled was complete extraction of the 

 haemolytic substances. Afterwards the extracts were fractioned under 

 the guidance of their more and more increasing activity. This 

 acti\ity was tested by dispersing the extracts in isotonic neutral 

 phosphate mixture at 37°*). 



The determination of the haemolytics was carried out in the 

 following way: 



The human blood obtained by venapunction was defibrinated and sharply 

 centrifiigalized at once The corpuscles were imbibed in fat -free filterpapers and 



I) NoGUCHi, Biochem. Zeitschr. VI. 327, (1907) 



-I See Landsteiner. Handbuch Kolle-VVassermann II, 1291, (1918) 



') Bhinkman, 1. c 



•'') See for the method Brinkman Arch, néerl. de Physiol. VI, 451, (1922). 



