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Scientific Proceedings (132) 



test this postulate on the living intestine in the following manner. 

 Loops of intestines were tied off in dogs, cats and rabbits under 

 anesthesia, and large inflow and outflow cannulas were attached 

 to the two ends of the same respectively. A solution of the drug 

 was perfused through the loop under proper precautions from 

 above downwards, maintaining the temperature of the animal 

 constant and a record was made of the blood pressure and res- 

 piratory effects. The drugs employed in these experiments were 

 solutions of potassium cyanide and the powerful alkaloid, 

 aconitin. These solutions were perfused at different rates as 

 indicated by the outflow per minute. It was found that when 

 the solution was perfused with slow speed the absorption was 

 much greater than when the rate of flow was more rapid. The 

 drugs may be perfused so rapidly that very little or no absorp- 

 tion of the poisons takes place at all. As illustrations of the 

 above may be given experiments performed on two cats on 

 December 21st, 1921. 



Each animal was anesthetized with ether and in each after 

 laparotomy a loop of intestine 30 cm. long was tied oft". Through 

 one of these a solution of potassium cyanide 0.5 per cent, was 

 perfused, at the rate of 100 c.c. per minute. In the other cat a 

 solution of the drug in the same concentration was perfused at 

 the rate of 500 c.c. per minute. It was found that the first 

 signs of poisoning as indicated by the respiration and blood pres- 

 sure curves in the first cat came on much earlier than in the 

 second cat and death occurred in the first experiment in less 

 than one-half of the time after which it occurred in the second 

 experiment. These results could be only interpreted on the as- 

 sumption that absorption took place much more rapidly in the 

 first cat than in the second. In another experiment, a dog was 

 used and a loop of intestines of the animal was perfused with 

 potassium cyanide, 1 per cent, solution. When the rate of per- 

 fusions was 200 c.c. per minute distinct signs of absorption were 

 noticed as indicated by the respiration and circulation. When 

 the rate of perfusion was increased to 700 c.c. per minute these 

 signs disappeared and apparently very little absorption took 

 place. Similar experiments were made in dogs and cats with 

 preparations of potassium cyanide and also of aconitin. The 

 results of these experiments indicated that the absorption was 

 much more rapid when the rate of flow through the intestines 

 was slow. 



