GALL BLADDER. 153 



Amyl nitrite causes relaxation of the gall-bladder as of other plain 

 muscular structures. 



Peptone. Ellinger 1 states that intravenous injection of peptone 

 causes contraction of the gall-bladder. We have found that the apparent 

 contraction does, indeed, occur when the gall-bladder and liver are left 

 in their natural relations. When arrangements are made to eliminate 

 the effect of swelling of the liver the apparent contraction completely 

 disappears, so that there can be no doubt that the increase of liver volume 

 caused by injection of peptone entirely accounts for the phenomenon. 



VI. THE QUESTION OF REFLEX ACTION THROUGH THE 

 CENTRAL NERVOUS SYSTEM. 



Heidenhain 2 attributed the first gush of bile, which he observed at 

 a certain interval after a meal, to the passage of acid chyme over the 

 biliary papilla causing a reflex stimulation of the gall-bladder. 



Bruno 3 , with a Pawlow fistula, did not observe this preliminary gush : 

 but it is evident that his experiment does not invalidate the conclusion 

 of Heidenhain, since the method of operation excludes contact of chyme 

 with the papilla. 



The discovery of secretin and its effect on secretion of bile suggested 

 another possible explanation of the effect described by Heidenhain. 

 The first effect of a rapid secretion of bile might cause a distension of 

 the gall-bladder, which, upon the analogy of the intestine, might react 

 by a sudden contraction. We have attempted to produce such an effect 

 by sudden distension of the balloon in the gall-bladder with water. We 

 observed no trace whatever of such a contractile reaction. 



On the other hand we do not find, under the conditions of our experi- 

 ments, any reflex effect on the gall-bladder contractions when acid (0'4 / 

 HC1) is injected into the duodenum or applied directly to the papilla, 

 or when the papilla is electrically stimulated. It is impossible, however, 

 to attach much significance to the failure to elicit such a reflex in an 

 anaesthetised animal. Further, it is not improbable that a reaction to 

 distension exists, which, like that of the urinary bladder, is dependent 

 on a reflex through the central nervous system and abolished by anes- 

 thetics. Our experiments, therefore, do not give any definite information 



1 Ellinger. Hofmeister's Beitrag. z. chem. Phys. u. Path. 1902. 



2 Heidenhain. loc. cit. 



3 Bruno. St. Petersburg Arch, des Soc. Biol. p. 87. 1899. 



