8G 



The HcBmolylic Action of Sodium Glycocholate. 

 By Ekic Pondek. 



(Communicated by Sir E. Sharpey Schafer, F.R.S. Received September 1-1, 1921.) 

 (From the Department of Physiology, University of Edinburgh.) 



Introduction. 



This paper contains a detailed investigation into the action of sodium 

 glycocholate, and into certain phenomena in which this salt plays an impor- 

 tant part. The presentation of this research is a matter of some difficulty, 

 since the observations recorded constitute merely the outlines of a very 

 complex subject. It has been thought best, even at the expense of some 

 lack of logical sequence, to present the problems more or less in the order in 

 which they presented themselves for solution, the reader being thus taken 

 over the several questions in the order in which they were investigated. To 

 avoid undue length, no detailed description of methods used is given, if such 

 description is to be found in a previous paper, on the findings of which this 

 work is based (1). 



The Physical Condition of Solutions of Bile Salts. 



Although there is no definite statement on the subject, the general opinion 

 appears to be that sodium taurocholate and sodium glycocholate form true 

 solutions in water. If this be so, it is remarkable that they possess properties 

 peculiar to colloids. If sodium taurocholate be dissolved in water, a clear 

 yellow solution results. This clearness soon disappears, the solution becomes 

 opalescent and, after about 12 hours, quite opaque. The opalescence is 

 caused, presumably, by the taurocholate passing into a physical state other 

 than that in which it was when first dissolved. The opalescent solution has 

 all the properties of a taurocholate solution ; its hsemolytie activity is as 

 great as is that of a clear solution of the same strength. A difference appears 

 on filtering the opalescent solution ; the filtrate has a less hemolytic power 

 than the original solution. This fact, together with the opalescence, suggests 

 that the taurocholate has assumed a less dispersed form. 



The more dilute the taurocholate solution is made, the more rapidly does 

 the opalescence appear ; in solution in 1 per cent, saline a similar occurrence 

 takes place, but less rapidly than in aqueous solution. 



Sodium glycocholate behaves in a similar way, but the appearance of the 



