480 IMMUNOLOGY 



These phenomena resemble tlie various ones produced by hista- 

 mine more closely than peptone at similar points on the blood 

 pressure curve. 



"4. A definite increase in coagulation time develops soon after 

 the shocking dose of antigen is administered. 



"5. A marked drop in the precipitin content of the blood oc- 

 curs after intoxication, but there is not a complete loss of pre- 

 cipitins. 



".6. A markedly engorged right heart with the lungs well col- 

 lapsed in rabbits dying of shock is observed. 



"7. The results of intestinal smootli muscle, kidney volume, in- 

 tracystie and intracranial pressures are variable and so frequently 

 negative as to be of no importance as an index of sensitization. 



"8. A definite fall occurs in body temperature during the ana- 

 phylactic shock. ' ' 



Some of his other observations have been mentioned earlier in the 

 chapter. 



Protracted Anaphylactic Shock in the Rabbit. — Coca (1927) 

 gives an excellent description of this phenomenon. The animal 

 may survive for varying lengths of time. Those that survive for 

 days or weeks show marked loss of weight (cachexia). 



Local Anaphylaxis or Arthus Phenomenon. — This has been 

 extensively studied by Opie (1924). He concludes that it is an 

 inflammatory reaction initiated by the meeting of antigen and 

 antibody in the tissues. His studies include observations on 

 reversed anaphylaxis. His published papers on anaphylaxis 

 should be read by the student. Opie's work on the Arthus Phe- 

 nomenon has been confirmed by Cannon and Marshall (1941). 



Anaphylaxis in the Dog. — Acute anaphylactic shock was first 

 observed in the dog by Richet and Portier (1902). Their descrip- 

 tion is given at the beginning of this chapter. The subject was 

 investigated extensively by Biedl and Kraus (1909) and by Pearce 

 and Eisenbrey (1910). They found that the characteristic physi- 

 ological picture in dogs under ether anesthesia is a profound 

 drop in blood pressure accompanied by extreme engorgement of 

 the liver and splanchnics. They also reported a prolongation of 

 the clotting time of the blood. A few other characteristic findings 

 were observed. In 1913 Auer and Robinson observed heart block 

 as occurring during acute shock. Manwaring et al. (1923, 1924) 



