PHYSIOLOGY AND BIOCHEMISTRY OF SHOCK 407 



4. A Summary of Some of the Physiological Changes 

 Accompanying Shock 



Bronchostenosis and asphyxia, labored breathing, a slow fall in 

 blood pressure, hemorrhages, intestinal congestion (guinea pig), fall 

 of blood pressure, congestion of liver and the corresponding congestion 

 of viscera (dog) are some of the common symptoms of anaphylaxis, 

 peptone and trypsin shock. Intravenous injection (dog) of trypsin 

 produces blood-clotting by converting prothrombin to thrombin before 

 an excess of heparin is released preventing clotting. In anaphylaxis 

 and peptone shock, the formation of a blood-clot does not occur. 



In dogs, vomiting, salivation, diarrhea, urination and collapse are 

 common to both anaphylaxis and trypsin shock. In rabbits, peptone and 

 anaphylactic shock cause thrombocytopenia; trypsin shock causes 

 leucopenia; and anaphylaxis produces either the aggregation of poly- 

 morphonuclear cells in the capillaries of the lungs, or a pneumonia. 

 Anaphylaxis causes spasmodic constriction of the pulmonary artery 

 followed by rapid dilatation of the right side of the heart and acute 

 heart failure, and in trypsin shock a marked rise in pulmonary artery 

 pressure occurs. 



In anaphylaxis and peptone shock there is a loss of histamine from 

 the liver to the plasma; in shock caused by trypsin liberation of hista- 

 mine has been claimed and contested. The principal chemical changes 

 in various shocks are characterized by the liberation of choline-like 

 substances, an increase of serum potassium, a decrease in serum alkali 

 reserve, an increase of lactic acid in the blood, a decrease in the con- 

 sumption of oxygen, and an increase in the secretion of urinary 

 creatine, uric acid and urea ammonia. 



5. Histamine Shock 



a. Eflfects of Histamine. The close resemblance between the phar- 

 macological effects of histamine in animals and those of anaphylactic 

 shock was pointed out by Dale and Laidlaw (1910). And Dale (1929) 

 proposed the theory that histamine is liberated from the tissues of 

 animals consequent to the interaction of antigen with antibody. This 

 theory of Dale has been supported by subsequent investigations. 



