346 STUDIES IN ADVANCED PHYSIOLOGY. 



The General Physiology of Bile. Our knowledge of 

 the physiological value of bile still leaves much to be de- 

 sired. Here more than with any other of the digestive 

 agents our knowledge is fragmentary, and there is at present 

 still no unanimity among leading physiologists as to the role 

 which it plays. It seems probable, however, that the intro- 

 duction of bile into the duodenum accomplishes the follow- 

 ing results : 



First. Bile is a slightly alkaline liquid, and as such 

 poured in large quantities into the intestine it overcomes 

 and destroys the acidity of the food as it comes from the 

 stomach, and so prepares the material for the pancreatic 

 digestion, which can only occur in an alkaline medium. 



Second. Bile possesses to a considerable extent the 

 property of emulsifying fats, and so materially assists 

 the pancreatic juice in this function. This property of 

 the bile is derived from the organic bile salts. It has 

 been stated by some physiologists that bile has the prop- 

 erty of splitting up pure fats into fatty acids, and so to as- 

 sist the steapsin of the pancreatic juice in the formation of 

 soaps. The emulsifying power of bile can be readily dem- 

 onstrated by simply shaking up bile and oil, the result of 

 which is a fairly stable emulsion. 



Third. Bile is a mild stimulant and so starts the peris- 

 taltic actions of the intestine. It has been observed that a 

 sudden gush of bile into the intestines will cause a peristal- 

 tic contraction to begin at that point and to creep slowly 

 downward. It would, so to speak, be nature's laxative and 

 the sluggishness of the intestines which follows the with- 

 holding of bile from them, as in various cases of bilious- 

 ness, may be partly explained in this way. This stimulat- 

 ing effect of the bile is again due to the glychocholic and 

 taurocholic acid salts. 



Fourth. It is asserted by some physiologists, but stren- 

 uously denied by others, that bile helps in the absorption 

 of fats. It was first stated that an animal membrane moist- 

 ened with bile would allow fats to traverse it more easily, 



