CHAPTER IV 



THE TOXIC OR EXCITING INJECTION 



Sensibilisin and the conditions which govern its appearance. 

 Different methods of carrying out the test injection; their 

 severity. Intracerebral test; its advantages. — Toxicity of 

 sera; its variations; its dosage. — Toxicity of milk; influence 

 of heat on the toxicity. — Specificity of the toxic effect. — 

 Toxicity of egg-albumen; its variations according to place 

 of injection. — Toxicity of heated egg-albumen; its speci6city. 

 — Symptoms of anaphylactic intoxication in the guinea-pig, 

 rabbit, dog, ox, horse, man. 



Now that we know how animals are sensitised, it 

 remains for us to investigate what takes place in the 

 organism after sensitisation has produced its effect. 

 At what point of time do the animals pass into the 

 anaphylactic state ? How is one to make sure of 

 this new state ? How is the toxic effect of the second 

 injection to be estimated ? Lastly, how can the 

 toxic effect of the latter be moderated ? 



We have already seen that sensitisation only be- 

 comes operative when a fixed interval of time elapses 

 between it and the second injection. This interval, 

 which is from eight to twelve days, is indispensable 

 for the production of a new body which we have 

 termed sensibilisin and which is none other than the 

 antibody of sensibiligen discussed in the preceding 

 chapter. 



Experiments shew, indeed, that the corollary of 

 every injection of sensibiligen is the appearance in 

 the serum of the animal of a special antibody which 

 is the material substratum of anaphylaxis. It is the 

 persistence of this antibody, of this sensibilisin, which 



27 



