BILE AND ITS FORMATION. 393 



of the collected bile that the fluid is not the result of a secretion of normal 

 liver bile. 



The quantity of bile secreted is, however, as shown by STADEL- 

 MANN, 1 subject to such great variation, even under physiological 

 conditions, that the study of those circumstances which influence the 

 secretion is veiy difficult and uncertain. The contradictory statements 

 by different investigators may probably be explained by this fact. 



In starvation the secretion diminishes. According to LUKJANOW 

 and ALBERTONi, 2 under these conditions the absolute quantity of solids 

 decreases, while the relative quantity increases. After partaking of 

 food the secretion increases again. The findings are very contra- 

 dictory in regard to the time necessary, after partaking of food, before 

 the secretion reaches its maximum. After a careful examination and 

 compilation of all the existing reports, HEiDENHAiN 3 has come to 

 the conclusion that in dogs the curve of rapidity of secretion shows two 

 maxima, the first at the third to fifth hour and the second at the thirteenth 

 to fifteenth hour after partaking of food. According to BARBERA 4 the 

 time when the maximum occurs is dependent upon the kind of food. 

 With carbohydrate food it is two to three hours, after protein food three 

 to four hours, and with fat diet it is five to seven hours, after feeding. 



According to earlier observations, the proteins of all the various 

 foods cause the greatest secretion of bile, while the carbohydrates dimin- 

 ish the secretion, or at least excite it much less than the proteins. 

 This coincides with the recent observations of BARBERA. The author- 

 ities are by no means agreed as to the action of the fats. While many 

 older investigators have not observed any increase, but rather the reverse 

 in the secretion of bile after feeding with fats, the researches of BARBERA 

 show an undoubted increase in the secretion of bile on fat feeding, greater 

 even than after carbohydrate feeding. According to ROSENBERG olive- 

 oil is a strong cholagogue, a statement which, according to other inves- 

 tigators MANDELSTAMM, Do YON and DUFOURT 5 has not been proven. 



As BARBERA has shown, a close relation exists between the bile 

 secretion and the quantity of urea formed, as an increase in the first 



1 Stadelmann, Der Icterus, etc., Stuttgart, 1891. 



2 Lukjanow, Zeitschr. f. physiol. Chem., 16; Albertoni, Recherches sur la secretion 

 biliaire, Turin, 1893. 



3 Hermann's Handb., 5, and Stadelmann, Der Icterus, etc. 



4 Centralbl. f . Physiol., 12 and 16. 



5 Barbara, Bull, della scienz. med. di Bologna (7), 5, Maly's Jahresber., 24, and 

 Centralbl. f. Physiol., 12 and 16; Rosenberg, Pfluger's Arch., 46; Mandelstamm, Ueber 

 den Einfluss einiger Arzneimittel auf Sekretion und Zusammensetzung der Galle (Dis- 

 sert. Dorpat, 1890); Doyon and Dufourt, Arch, de Physiol. (5), 9. In regard to the 

 action of various foods on the secretion of bile see also Heidenhain, 1. c.; Stadelmann, 

 Der Icterus; and Barbera, 1. c. 



