GENERAL CONCLUSIONS. 569 



Rutherford, Vignal, and Dodds have experimented with a very- 

 large number of drugs, which were injected, dissolved in bile, into the 

 duodenum. 1 The action of certain of these drugs has been re-investi- 

 gated by Paschkis 2 and by Lewaschew, 3 whose results do not in all cases 

 confirm those of the previous observers. It is, however, unnecessary to 

 consider them in detail. Naunyn 4 sums up the matter by saying, 

 "Many substances, when taken into the stomach, and more surely 

 still when introduced into the duodenum (Rutherford), appear to pro- 

 duce under certain conditions a slight increase of the biliary secretion. 

 But the influence of these substances upon the secretion of bile is 

 uncertain, and never a potent one." 



GENERAL CONCLUSIONS. 



From a study of the mechanism of bile secretion, it is manifest that 

 in its bile-producing function the liver differs from most other glands, 

 since its activity is not under the direct control of the nervous system, 

 but is modified by the ebb and flow of the blood stream, and by the 

 influence of various chemical substances, such as the salts of the bile 

 acids. 



The relationship of bile secretion to the other functions of the liver 

 is in many points still obscure. That the disintegration of haemoglobin 

 and the formation of bile pigments are closely connected, is definitely 

 known (p. 563). That these two functions are connected with the 

 production of urea, is shown by the fact that the administration of haemo- 

 lytic agents, such as toluylenediainin, pyrogallic acid, etc., which increase 

 the formation of bilirubin, cause a proportionate increase in the dis- 

 integration of red blood corpuscles, and in the excretion of urea. 5 



How far the formation of the amido-acids of the bile salts is con- 

 nected with the disintegration of proteids, cannot be considered as 

 settled, but the evidence adduced on p. 562 suggests that such a 

 relationship exists. If this be the case, the formation of biliary con- 

 stituents must be connected with .the manufacture of glycogen and 

 glucose from proteids. The formation of bile seems independent of the 

 mere accumulation of carbohydrates in the liver. 



The various compounds of fatty acids in the bile are probably 

 derived from the fatty acid compounds stored in the liver (p. 564). 

 The nucleo-proteid, the mucin, and the cholesteriri are probably to be 

 regarded, not as true biliary constituents, but as products of the bile 

 passages. As to the relationship of the inorganic salts of the bile 

 with the other hepatic functions, nothing is known. 



1 Rutherford, loc. cit. 2 Loc. cit. 3 Loc. cit. 



"Cholelithiasis," translated by A. E. Garrod, New Syd. Soc., p. 172. 

 5 Noel Paton, Brit. Med. Journ., London, 1886, vol. ii. p. 207. 



