On the Specificity and Action in Vitro of Gastrotoxin. 



427 



I. Action in Vitro. 



In my first communication I stated that the blood serum of the rabbit 

 injected with stomach cells washed free from blood became more highly 

 hemolytic for guinea-pig's red-blood corpuscles than it was previous to 

 injection. I have recently been able to demonstrate that two distinct 

 hamiolysins are produced during the process of immunisation. 



The gastrotoxin has likewise the power of producing marked changes in 

 the soluble proteids, and also in the protoplasmic granules of the gastric 

 •cells. It further brings about slight though definite changes in the intact 

 ■cells themselves. 



1. Hcemolytic Action. 



Method. — In obtaining the guinea-pig's blood corpuscles to test the 

 hemolytic power of the immunised rabbit's serum, the blood is whipped and 

 •centrifugalised, the serum then pipetted off and the corpuscles washed in 

 0'36-per-cent. salt solution several times. A 5-per-cent. suspension of the 

 corpuscles in salt solution is used for testing the serum. 



A known quantity, usually 1 c.c, of this suspension of corpuscles is mixed 

 with diminishing amounts of the serum in a series of test-tubes, the volume 

 •of fluid in each tube being made up to the same amount with salt solution. 

 The kibes are placed in the incubator for one hour, and then in the ice 

 •chamber till the following morning, when the exact point at which the 

 corpuscles are completely dissolved can be determined with ease. 



As an example, the details of the following experiment which was made to 

 determine the normal hemolytic power of a rabbit's blood for guinea-pig's 

 corpuscles are given : — 



Corpuscles 

 (5 per cent, 

 suspension). 



c.c. 

 1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 



Normal rabbit's 

 serum. 



Salt solution. 



2-25 

 2 



1 -75 

 1 -5 

 1-25 

 1 



0-75 

 5 

 0-25 



Ws - 10-025 



Diluted IT !, 



100 

 time; 



n J -0075 



e< I ' 005 

 LO-0025 



c.c. 

 0-25 



5 



0- 75 

 1 



1 -25 



1- 5 



•75 



■25 



1 



2-25 I 

 2-5 }- 

 2-75 | 

 2 J 

 2-25 



After 1 hour's incubation and ice 

 chamber. 



Complete solution. 



Almost complete. 

 Incomplete. 



Fluid above corpuscles uniformly 

 tinted. 



Fluid tinted to diminishing heights 

 above corpuscles. 



No latins. 



