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Scientific Proceedings (129) 



fluid continues to pour out of the trachea almost as fast as it 

 escapes from the efferent canula. 



To our mind the increased capillary permeability thus demon- 

 strated is the most significant feature of these reactions. We 

 believe that increased specific capillary permeability will ultimate- 

 ly be shown to be the dominant fundamental factor in protein 

 sensitization, to which all other anaphylactic phenomena are 

 secondary. This view is in accord with clinical evidence. 



131 (2091) 



Types of canine anaphylaxis. 



By W. H. MANWARING, R. C. CHILCOTE, and V. M. HOSEPIAN. 



[From the Laboratory of Experimental Pathology, Stanford 

 University, California.] 



The typical anaphylactic reaction in dogs is characterized by 

 a sudden, pronounced fall in arterial blood pressure. The pres- 

 sure is usually reduced to about 25 mm. Hg. by the end of 

 ninety seconds. This typical reaction is demonstrable in prac- 

 tically all dogs tested from eighteen to twenty-four days after 

 intravenous horse serum sensitization. Recovery usually takes 

 place in from one to two hours, depending upon the severity 

 of the reaction. 



We have recently encountered an example of a second type of 

 canine anaphylaxis. This was in a dog tested during the seventh 

 week of horse serum sensitization. In this dog no change in 

 arterial blood pressure took place for four minutes after intra- 

 venous serum injection. The pressure then fell slowly and ir- 

 regularly, death occurring in nine and one-half minutes. 



The thorax of this dog was immediately opened. The lungs 

 were found almost non-collapsible, but could be readily collapsed 

 on pressure. This partial pulmonary fixation passed off in about 

 fifteen minutes. The blood was rendered non-coagulable by the 

 reaction, but slight hepatic changes were noted at autopsy, and 

 no duodenal hemorrhage. The pathological findings resembled 

 those of guinea pig anaphylaxis. 



