PHYSIOLOGY AND BIOCHEMISTRY OF SHOCK 441 



exercise predominantly a proteolytic function. If we assume that a 

 proteolytic action precedes, or is necessary, for anaphylactic reactions, 

 the antibody synthesizing proteinase might readily assume a proteolytic 

 function in an injured tissue. Or in non-antibody producing cells local 

 proteinases can assume such a role. Our concept, in contrast to that of 

 Rocha e Silva, does not provide a preliminary reaction to activate 

 cellular cathepsins. They are there in active form to regulate the 

 synthesis and proteolysis of proteins. Under injurious conditions 

 cathepsins simply assume predominantly a proteolytic role. In this way, 

 the disturbed equilibrium of reactions in damaged tissues can lead to 

 proteolysis and thus account for the increased non-protein nitrogen in 

 the humoral system in various pathological conditions, and an increase 

 non-protein nitrogen excretion in the urine of animals subjected to 

 anaphylactic shocks. In this connection reference needs to be made 

 to the results of a study by Ungar (1947). He reported that the addi- 

 tion of specific antigen to tissues— lung, liver, kidney— of sensitized 

 guinea pigs causes the liberation of a protease. TTie same results were 

 obtained by adding peptone to normal guinea pig tissues. Only minute 

 amounts of enzyme were detected in the experimental conditions used 

 in this study. However, Ungar and Mist (1949) found that fibri- 

 nolysin was liberated by adding the specific antigen to serum from 

 sensitized guinea pigs. 



1 1 . Summary 



An attempt to formulate a reasonable concept concerning the 

 mechanism of anaphylaxis necessitates a recapitulation of the pertinent 

 reactions. The anaphylactic reaction is violent and explosive in char- 

 acter. It is associated with profound disturbances in the respiratory, 

 circulatory, glandular and smooth muscle systems. The antigen-anti- 

 body reaction, occurring in a cellular environment, causes injury 

 to cells. In severe cases, it is fatal; in mild cases it may be reversible. 

 These manifestations result in, or are associated with abnormal 

 metabolic changes. 



In anaphylaxis, there is first quickening of respiration, followed by 

 stenosis of the bronchioles due to direct action on the muscular walls 

 of the bronchi, leading to asphyxia. An initial moderate rise in systemic 

 blood pressure, most likely due to the stimulation of the sympathetic 



