PHYSIOLOGY OF CYTOST ACTION 79 



suffices to cause an accumulation of blood in the 

 splanchnic area and consequently the animal mani- 

 fests the outward symptoms of shock. Such an animal, 

 however, will usually recover when returned to its 

 natural position. In this respect, postural shock dif- 

 fers from the profound state of shock induced by tis- 

 sue damage. It follows, therefore, that the production 

 of true shock entails something more than a mere re- 

 versible accumulation of blood in the splanchnic area, 

 as is the case in postural shock. 



At this point we may recall the author's observa- 

 tions, mentioned previously, that in experimental 

 shock the blood was found to clot more readily than 

 is normally the case, and the serum from animals in 

 profound shock contained substances capable of ef- 

 fecting hemagglutination and coagulation of blood 

 drawn from intact animals. Such being the case, it 

 follows that such processes may take place within the 

 blood vessels. Thus, the blood which accumulates in 

 dilated vessels may suffer a partial or complete coagu- 

 lation, the extent of this process depending upon the 

 amount of coagulins present in the blood. In any 

 case, even though the extent of agglutination and co- 

 agulation be slight, the net effect will be to raise the 

 viscosity of the blood and thus hinder its passage 

 through the vessels and thence mechanically to dis- 

 tend the vessels even more. 



Leo Loeb ( 1904) has shown that coagulins may be 

 extracted from tissues and this fact is in harmony 

 with the author's concept that shock is produced pri- 

 marily by the products of cellular disintegration. 



As a result of the agglutination and coagulation of 

 the blood, the capillaries may be easily blocked, thus 



