PROTEIN SENSITIZATION OR ANAPHYLAXIS 293 



"The hypothetical vasodilatine must, therefore, be 

 regarded as consisting of at least two substances: 



"1. /3-iminazolylethalamin, causing fall of blood-pressure, 

 and the other characteristic effects on plain muscle and 

 gland cells, but not affecting coagulation of the blood. 



"2. Another substance, or other substances, which renders 

 the blood incoagulable, and which may or may not play 

 some part in the other effects." 



Friedberger and Moreschi 1 conclude from its behavior 

 toward alkalies that it is not the true anaphylactic poison 

 which they believe to be the anaphylatoxin of Friedberger. 



Biedl and Kraus 2 hold, contrary to Barger and Dale, 

 that /3-i does delay the coagulation of blood in dogs. They 

 say: "In dogs 3 mg. of this substance causes immediate 

 fall in blood-pressure, retards the coagulation of the blood, 

 and induces the phenomena of anaphylaxis." 



With our poison, /3-i seems to agree closely. Both induce 

 bronchial spasm and distention of the lungs in guinea-pigs, 

 and cause prompt and marked fall in blood pressure in 

 dogs. Neither destroys the coagulability of the blood. 

 In the purest form in which we have obtained it our poison 

 kills guinea-pigs intravenously in doses of 0.5 mg., and this 

 is the fatal dose of /3-i. When the active agents in our 

 crude poison are isolated we shall not be surprised if /3-i 

 or some closely allied body is among them. 



/3-i has been prepared by Barger and Dale from the 

 mucosa of the small intestine of the ox by boiling with 0.1 

 per cent, of hydrochloric acid, and further treatment with 

 silver nitrate, and excess of baryta, according to the method 

 of Kutscher. In regard to this work they make the following 

 statement: "We have no evidence with regard to the origin 

 of the /3-i in the extract of intestinal mucosa. All possible 

 precautions were taken to avoid putrefaction before the 

 material was worked up. Moreover, a piece of intestine 

 removed immediately after death, or even during life, from 



1 Berl. klin. Woch., 1912, No. 16. 



2 Zeitsch. f. Immunitatsforschung, 1912, xv, 447. 



