404 IMMUNO-CATALYSIS 



blood-pressure than that observed following a similar injection into 

 the femoral vein. 



In rabhits, intravenous injection of trypsin results in a momentary 

 rise and more conspicuous fall in systemic blood pressure, a marked 

 rise in pulmonary arterial pressure, a marked leucopenia, and a partial 

 to marked incoagulability of the blood. With increased amounts of 

 trypsin injected intracutaneously a local necrosis comparable to that of 

 the Arthus reaction is produced. 



With guinea figs, the intravenous injection of trypsin is rapidly 

 fatal. On opening the chest the lungs collapse and show areas of local 

 hemorrhage. The gross appearance indicates that death is due to an 

 embolic phenomenon, and to an asphyxia resulting from broncho- 

 stenosis. 



In cats, the intravenous injection of trypsin results in a fall in the 

 systemic blood pressure and a decreased clotting of the blood. 



b. Papain and Ficin. Rocha e Silva (1943) reported that ficin and 

 papain are toxic upon intravenous injection. Molitor, et al. (1941) 

 reported the results of a study on the toxicity of ficin in mice, rats, 

 guinea pigs, rabbits, cats, and dogs. They found that sublethal intra- 

 venous administration of ficin produced vomiting, bloody diarrhea, and 

 general prostration. Autopsy showed severe irritation of the gastro-in- 

 testinal tract ranging from inflammatory reactions to erosions. Small 

 doses of ficin reduced the erythrocyte count and markedly prolonged 

 the blood clotting time. Parenteral injection of ficin caused severe 

 tissue damage. 



c. Chymotrypsin. The effects of chymotrypsin have been reported 

 to be less potent than trypsin although they are qualitatively similar 

 (Rocha e Silva, 1943). 



Tagnon, et al. (1945) compared the symptoms of shocks produced 

 by trypsin and chymotrypsin. They pointed out that trypsin brings 

 about intravascular clotting when it is injected intravenously and, 

 therefore, it is difficult to evaluate in a given experiment what changes 

 result from the clotting activity and what changes result from the 

 proteolytic activity of trypsin, since clotting agents such as thrombin, 

 and proteolytic agents such as trypsin, both produce shock in animals 

 (Tagnon, 1945). Because of the fact that trypsin brings about intra- 



