Intestinal Absorption 



455 



In another series of experiments, the authors put to test a 

 different idea. It was thought interesting to determine in which 

 way and to what extent intestinal peristalsis would influence the 

 absorption of drugs from closed loops of intestine. To deter- 

 mine this point, experiments were made with the dye, phen- 

 olsulphonphthalein. A loop of intestine was tied off in a cat 

 under anesthesia and 1 c.c. of phenolsulphonphthalein diluted in 

 10 c.c. of water was injected into the same. At the end of one 

 hour the animal was killed, the intestinal loop was excised and 

 the dye remaining therein was carefully rinsed out with alkaline 

 solution and the amount of drug quantitatively determined by 

 colorimetric methods. Another cat was treated in the same way. 

 An intestinal loop of the same length was made, the same amount 

 of dye and water was injected, but in addition to this the animal 

 was given a hypodermic injection of a small dose of pilocarpin 

 in order to stimulate intestinal peristalsis. At the end of one 

 hour the amount of dye in the intestines and hence, the amount 

 of dye absorbed was determined as above. In a third cat a sim- 

 ilar experiment was performed but in this cat intestinal peri- 

 stalsis was inhibited by an injection of atropin and after one 

 hour, the amount of absorption was again color imetrically deter- 

 mined. It was found that after mild stimulation of intestinal 

 peristalsis, as for instance with small doses of pilocarpin (0.2 

 mgm. per kilo) absorption also was greater than in a normal cat. 

 On the other hand, after inhibiting the peristalsis with atropin 

 or with other drugs, absorption was not as great, as illustrated 

 by the following experiments. 



Cat A. Loop of 30 cm. injected, 1 c.c. of phenolsulphonph- 

 thalein in 10 c.c. water. Absorption at the end of one hour, 55 

 to 60 per cent. 



Cat B. Intestinal loop of the same length and the same 

 amount of phenolsulphonphthalein was injected. The cat was 

 given a hypodermic injection of pilocarpin hydrochloride (0.2 

 mgm. per kilo). At the end of one hour the amount of dye 

 absorbed was 80 to 90 per cent. 



Cat C. Similar loop of intestines was injected with the same 

 amount of dye. Atropin sulphate, 1 mgm., was given to this 

 cat. Amount of dye absorbed at the end of one hour was 40 

 per cent. 



In another series of experiments the intestines were paralyzed 

 by an intraperitoneal injection of a 1 per cent, solution of benzyl 



