Blood Coagulation. 



83 



Experiment 6. 



Effect of a Large Dose of Refined Pancreatic Rennet on the 

 Coagulation of the Blood (Cat). 



4 c.c. of a refined pancreatic rennet (equal to 38 c.c. of a 3 per cent. sol. of the 



crude sol.) was used. 



Clotting time before injection minutes. 



Clotting time 2 minutes after injection 3 minutes. 



Clotting time 5 minutes after injection 5 minutes. 



Clotting time 10 minutes after injection 15 minutes. 



Clotting time 25 minutes after injection 6 minutes. 



Thus we find after an initial diminution of the clotting time 

 there was a prolongation and a return to normal at the end of 

 25 minutes. 



THE EFFECT OF RENNETS FROM OTHER SOURCES ON THE 

 COAGULATION OF BLOOD. 



On account of the striking action of pancreatic rennet in 

 hastening of coagulation of the blood in vitro, studies have been 

 undertaken with rennets from other sources, for purposes of com- 

 parison. The action of these rennets on blood coagulation may 

 possibly be less potent than that of the pancreatic variety. The 

 isolation of the pure rennet from the stomach has thus far been 

 difficult to accomplish. In one experiment we used a crude pepsin 

 solution of known milk coagulating power and found a distinct 

 delay in the coagulation of the blood (see Exp. 7). This action 

 may possibly be due to the impurities in the crude pepsin-rennet 

 solution. 



Experiment 7. 



Citrated plasma 0.5 c.c. 0.5 c.c. 0.5 c.c. 0.5 c.c. 0.5 c.c. 



Crude pepsin — 5 per cent o 1 gtt. 2 gtt. 3 gtt. 4 gtt. 



CaCh — 1 per cent 2 gtt. 2 gtt. 2 gtt. 2 gtt. 2 gtt. 



Clotting time 8 min. 7 min. 25 mm. none none 



at the end of 24 hours. 



Conclusions. 



1. Pancreatic rennet shows great activity as a coagulant for 

 normal and hemophilic blood. 



2. Intravenous injection of pancreatic rennet does not produce 

 anaphylaxis. 



3. Moderate intravenous doses diminish the coagulation time, 

 and excessive doses increase the coagulation time after an initial 

 shortening. 



