5<5 



MECHANISM OF BILE SECRETION. 



of fluid, about 70 c.c. per diem, is continually secreted from the walls of 

 the gall bladder. 1 How far this fluid is a physiological secretion, and 

 how far it is due to pathological conditions, is difficult to decide. 



That water is secreted by the liver cells, as well as by the cells of 

 the ducts, is proved by the way in which pigments, 2 which are secreted 

 by the liver cells alone, are washed down into the bile passages. 



The elimination of the water of the bile is a process of secretion, 

 and not of transudation. Heidenhain's observations on the relative 

 pressures in the bile passages and in the blood vessels passing to the 

 liver, 3 given in the following table, demonstrate very clearly that, though 

 the pressure of secretion of bile is low, it is nevertheless considerably 

 higher than the blood pressure in the portal vein. 



The absorption of water from the alimentary canal seems under 

 certain conditions to increase the secretion of water by the liver. 



Eohrig, 4 Bidder and Schmidt, 5 and Zalesky, 6 noticed that the intro- 

 duction of water into the stomach and intestine of dogs with biliary 

 fistulas increased the flow of bile. Eosenberg 7 found that if the intestine 

 had previously been cleared oub by a glycerin enema, the introduction 

 of 500 c.c. of water into the intestine increased the flow of bile. In a 

 case of complete biliary fistula in a woman, 8 the amount of the bile 

 secretion was greater upon the days on which a large quantity of fluid 

 was taken, and this increase was in the water of the bile, not in the 

 solids. 



Inorganic salts. The analyses of the bile of the dog given by 

 Hoppe-Seyler, 9 show that in bile taken from the gall bladder the salts 

 constitute about 5 per cent, of the solids, while in freshly secreted bile 

 they amount to about 13 or 14 per cent. The freshly secreted bile 

 alone need be considered in discussing the mode of formation of these 

 salts. A comparison of the salts of the bile with the salts of the blood 

 plasma indicates that the percentage amount of salts is smaller in bile 

 than in blood, and that, while chloride of sodium is the most abundant in 



1 Birch and Spong, Journ. PhysioL, Cambridge and London, vol. viii. p. 378 ; Mayo 

 Robson, Proc. Roy. Soc. London, 1890, vol. xlvii. p. 499. 



- Wertlieimer, Arch, dephysioL norm, etpath., Paris, 1891, p. 724. 

 3 Hermann's "Handbnch," Bd. v. S. 269. 



* Med. Jahrb., Wien, 1873, Bd. ii. 



5 " Die Verdauungssafte," 1852, S. 166. 



6 Hermann and Schwalbe, Jaliresb. ii. d. Fortschr. d. Anat. u. PhysioL, Leipzig, 1877, 

 S. 219. 



7 Arch./, d. ges. PhysioL, Bonn, 1890, Bd. xlvi. S. 361. 



8 Noel Paton and Balfour, Rep. Lai. Roy. Coll. Phys., Edin., 1891, vol. iii. p. 191. 



9 "PhysioL Chem.," S. 302. 



