| Autor: |
Van Der Lingen, J. S., Macht, D. I. |
| Zdroj: |
Experimental Biology and Medicine; May 1923, Vol. 20 Issue: 8 p453-456, 4p |
| Abstrakt: |
The following experiments were suggested by purely biophysical considerations concerning absorption from the intestines and it was deemed desirable to report the same in this preliminary communication.On purely physical-chemical grounds it can be shown that the absorption of a chemical in solution which flows through a membranous tube will depend on the speed of flow of the solution through the lumen of the tube. The authors attempted to 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 respiratory 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 perfusetl with slow speed the absorption was much greater than when the rate of flow was more rapid. The drigs may be perfused so rapidly that very little or no absorption of the poisons takes place at all. As illustrations of the above may llre given experiments performed on two cats on December 21st, 1921.Each animal was anesthetized with ether and in each after laparotmy a loop of intestine 30 cm. long was tied off. 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 pressure cilrves 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 |
| Databáze: |
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