CHAP. VI.] CHOLAGOGUES. 371 



various substances to increase tfie amount of bile in the dejections. 

 He observes dejections of a clay colour, he gives five grains of 

 calomel, and further observes x that in some cases the dejections 

 thereafter assume their natural appearance. He cannot be certain 

 of the manner in which this result is brought about. For anything 

 he knows, it might be occasioned (1) by stimulation of the hepatic 

 secreting apparatus ; or (2) by the stimulation of the muscular fibres 

 of the gall-bladder and larger bile-ducts to wit the bile-expelling 

 apparatus ; or (3) by removing a catarrhal or congested state of the 

 orifice of the common bile-duct, or of the general extent of the 

 larger bile-ducts ; or (4) by removing from the intestine substances 

 which had been passing therefrom into the portal vein and depressing 

 the action of the hepatic cells ; or (5) by stimulating the intestinal 

 glands, and thus producing drainage of the portal system, whereby 

 the ' loaded ' liver might possibly be relieved 1 ." 



In truth, the investigation of cholagogues is one of the most 

 difficult in the whole range of pharmacology, for the various methods 

 of research which have hitherto been employed are all, more or less, 

 open to objections which compel the utmost caution in drawing 

 inferences from them, and have led to the most contradictory results. 



The first observations on the cholagogue action of a drug had 

 reference to calomel and were performed on dogs with biliary fistula. 

 " By this method, Nasse 2 , Kolliker and Muller 3 , Scott 4 , severally made 

 observations on a single dog with reference to the effect of calomel 

 on the biliary secretion. Being in some measure contradictory, the 

 subject was in 1866 taken up by a committee, of which the late 

 Professor Hughes Burnett was chairman and reporter 5 . Professor 

 Arthur Gamgee and the Author were the two junior members of the 

 committee upon whom devolved the task of performing the experi- 

 ments. The investigation was laborious and lasted two years 6 ." The 

 conclusions arrived at by this committee were that calomel, mercuric 

 chloride and taraxacum do not increase the flow of bile but probably 

 act on the bile expelling apparatus. 



" In 1873 Rohrig 7 observed the rate of biliary flow from temporary 

 fistulse in fasting curarised dogs, before and after the injection of 

 purgative agents into the stomach or intestine. He found that large 

 doses of croton oil greatly increased the secretion of bile and that a 



1 W. Rutherford, ' An Experimental Research on the Physiological Action of Drugs 

 on the Secretion of Bile.' (From the Transactions of the Royal Society of Edinburgh, 

 Vol. xxix.). Edinburgh, 1879. 



2 J. H. Nasse, Commentatio de bilis quotidie a cane secretae copia et indole.' 

 Quoted by Rutherford. 



3 Kolliker und Muller, Beitrag zur Lehre von der Galle.' Wiirzburg. Verhandlungen, 

 Vol. v. (1855). Quoted by Rutherford, p. 231. 



4 G. Scott, ' On the influence of mercurial preparations on the secretion of bile.' 

 Beale's Archives of Medicine, Vol. i. p. 209. 



5 British Association Reports, 1868. 



6 Rutherford, op. cit. p. 136. 



7 Rohrig, ' Experimentelle Untersuchungen iiber die Physiologic der Gallenabson- 

 derung.' Wiener med. Jahrbiicher, 1873, p. 240. 



242 



