406 INFECTION AND RESISTANCE 



Biedl and Kraus have found a similar parallelism in guinea pigs 

 in which they determined the typical bronchial spasms after peptone 

 administration. This is in contrast to Werbitzky, 69 who found even 

 large doses of peptone non-toxic for guinea pigs. Nevertheless, there 

 is no question that the similarity between peptone shock and anaphy- 

 laxis is very striking and of great theoretical importance. It does 

 not, however, bring us much nearer to a chemical understanding of 

 the nature of the poisons since the "Witte" peptone used in these ex- 

 periments is a mixture of many different substances. Brieger, 70 

 for instance, found toxic and non-toxic lots of Witte peptone. The 

 toxic ones yielded on extraction a body which he calls peptotoxin. 

 This variation in the constitution of different samples of so-called 

 "pepton" may account for some of the conflicting results obtained in 

 guinea pigs. 71 



Recently Dale has suggested that B-imidazolethylamin or his- 

 tamin may be the active principle concerned in anaphy lactic shock. 

 Intravenous injection of 0.5 mg. of this substance into large guinea 

 pigs results in typical respiratory difficulties, convulsions with death 

 and distention of the lungs typical of anaphylactic shock. Treat- 

 ment with atropin diminishes this action, just as Auer and Lewis 

 found this to be the case in true anaphylaxis, and fall in blood 

 pressure also occurs. It would seem then that substances represent- 

 ing cleavage . products of native proteins of highly complex nature, 

 the result of proteolytic cleavage not very far advanced, are prob- 

 ably concerned in the production of anaphylactic shock. The ana- 

 phylatoxins of Friedberger cannot of course be studied chemically 

 by the methods to which Vaughan's poisons are amenable. 



PHENOMENA CLOSELY RELATED TO ANAPHYLAXIS 



There are a number of well-defined phenomena of acquired 

 hypersusceptibility or sensitiveness which, in nature, seem closely 

 analogous to true anaphylaxis as we understand it to-day, but re- 

 garding the mechanism of which the opinions of experimenters are 

 still to some extent at variance. 



Among the most important of these is the toxic action of normal 

 sera when injected into animals of another species a phenomenon 

 which is now generally accepted as belonging in principle to the true 

 ;anaphylactic phenomena, though this opinion is of comparatively 

 recent formulation. The subject is of sufficient theoretical and 

 practical importance to be considered in some detail. 



The older studies of phenomena belonging to this category fol- 



69 Werbitzky. C. R. de la Soc. de Biol., Vol. 66, 1909. 



70 Brieger. "Die Ptomaine/' 1, p. 14. 



71 For analysis of Witte peptone, see Hammarsten, "Physiological Chem- 

 istry," English translation. 



