AND ABSORPTION 49 



The erepsin had converted the peptone into amino- 

 acids. 



We must not hope, therefore, when we feed a 

 patient on peptonized foods, that we have completely 

 saved him the necessity of digesting them. We have 

 carried the process only part of the way. It is not 

 feasible, perhaps, to feed him on aminoacids, because 

 the prolonged pancreatic digestion makes the food 

 unpleasantly bitter and might cause diarrhoea ; 

 aminoacids are not normal occupants of the stomach. 

 But there may be a future for rectal feeding with the 

 products of a pancreatic digest extending over two 

 days. In giving nutrient enemata of peptonized 

 milk we take the presence of erepsin in the mucous 

 membrane of that particular patient's rectum on 

 trust. Sometimes the patient seems to starve 

 although having nutrients. If we gave him amino- 

 acids instead of peptones, we might remove at least 

 one difficulty in the way of nourishing him. 



FUNCTIONS OF THE COLON. 



Motor Functions. We have always known that 

 the small intestine is continually in movement, the 

 main character of the movement being an onward 

 sweeping wave called peristalsis, carrying the bowel 

 contents from the stomach to the colon. Peristalsis 

 consists of a wave of relaxation pursued by a wave 

 of constriction. It is controlled by a purely local 

 mechanism, and will go on after all nerves have been 

 severed, or even after cutting the intestines right 

 out of the body. After cutting the bowel across the 

 wave is stopped at the point of division. Fortunately 



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