150 ANAPHYLAXIS 



the symptoms, if the animal is previously anesthetized with ether 

 or ethyl chloride, or is treated with hypnotics, such as urethaiie, 

 paraldehyde or chloral hydrate. 



Biedl and Kraus, on the other hand, working with dogs, came to 

 the conclusion that primary injury to the brain can probably be 

 excluded, since paralysis and respiratory disturbances were not 

 observed and the reflexes did not disappear. They could note as 

 a constant symptom, however, a marked drop in blood pressure 

 (from 120 to 150 Hgmn. to 80, 60, and even 40), which was shown 

 to be of peripheral origin, and they are inclined to attribute 

 practically all other symptoms, which have been noted during the 

 anaphylactic reaction, including the drop in temperature which is 

 seen in all cases, to this one factor. The effect of the narcotics and 

 hypnotics they explain by the assumption that these remedies 

 merely render the central nervous system less susceptible to the 

 effect of stimuli resulting from the drop of blood pressure and 

 the consequent central anemia. 



Auer and Lewis also assume a peripheral origin of the anaphyl- 

 actic symptom complex, but regard the spasmodic contraction of 

 the smallest bronchioles which is so constantly seen in guinea-pigs 

 as the essential factor, in these animals at least. It would thus 

 appear that in different animals the mechanism may be different, 

 but the possibility must also be borne in mind that these differences 

 may be more or less accidental and not essential. This idea is 

 supported by the observation of Schultz and Jordan that the bron- 

 chial mucous membrane of guinea-pigs is especially thick and folded 

 in such a manner, that relatively slight contractions of the muscle 

 fibres, which in other animals would lead to no untoward results, 

 might be sufficient in the guinea-pig to effect complete occlusion 

 of the bronchial lumen. Evidently, however, our knowledge of 

 existing conditions is as yet too meagre to warrant any far-reaching 

 conclusions. 



Mechanism of Antianaphylaxis. As regards the mechanism which 

 underlies the production of antianaphylaxis we likewise know very 

 little. Friedberger suggested that it might be due to the absorption 

 of whatever antibody was already formed by the antigen injected 

 before the period of "susceptibility" is reached, and that a reinjec- 

 tion during that period can then not give rise to any deleterious 

 effects since either no antibody is available at all, or because it is 



