FIRST STUDIES ON ANAPHYLAXIS 7 



Nothing gives a better idea of the intensity of the 

 phenomenon, according to Richet, than the difference 

 between these two cases. In the case of the normal 

 dog there was no vomiting even with a dose of 

 o-o8 gr. ; in that of the sensitised dog vomiting occurred 

 with a dose of o-ooi gr. The anaphylactic state there- 

 fore renders the animal eighty times more sensitive 

 in the particular instance of poisoning by congestin. 



The first work of Portier and of Richet dates from 

 1902. 



In the following year (1903) Arthus published an 

 account of his researches on the hypersensitiveness 

 of rabbits in the presence of horse serum. ^ Upon 

 renewing the injections at set intervals, he noted 

 that the serum was first of all reabsorbed without any 

 difficulty. But when the fourth injection was made 

 the serum set up a local infiltration. This infiltra- 

 tion, mild to commence with, became indurated after 

 the fifth injection, and would assume a gangrenous 

 appearance after the later injections. The same 

 local phenomena were observed when the first in- 

 jection was made intraperitoneally and the subse- 

 quent ones hypodermically. 



Moreover, Arthus discovered that it was possible 

 to produce serious disturbances and even death in 

 rabbits which had received several doses of serum 

 subcutaneously, by afterwards injecting them with 

 the serum intravenously. 



It was found possible to produce analogous pheno- 

 mena by means of treatment with milk. These 

 phenomena were exhibited in a strictly specific 

 fashion — that is to say, the animals treated at first 

 with milk only appeared sensitive to a further in- 

 jection of milk and not to an injection of serum. As 

 was stated by Arthus, " the rabbit sensitised by and 

 for serum is not so for milk, and vice versa." 

 ^ Compies rend. Soc. de Biol., 1903, Iv., p. 817. 



