Physiology of the Gall Bladder. 117 



alter their permeability to sodium chloride, whereas membranes 

 prepared under the same conditions containing fifty per cent, of 

 "Lecithin" by weight become relatively semi-permeable with de- 

 creasing drying times. 



II. Changes in the sizes of the aggregates of the lecithin 

 molecules is suggested as a possible influence on the permeability 

 of the lecithin-collodion membranes. 



56 (1803) 



Notes on studies in the physiology of the gall bladder. 



By LIONEL S. AUSTER and BURRILL B. CROHN. 



[From the Laboratory of Physiology, Cornell University 

 Medical College, New York City.] 



In undertaking the following animal experiments on the nature 

 of the expulsive action of the gall bladder, we had particularly in 

 mind the investigation of the modus operandi of magnesium 

 sulphate when applied to the papilla of Vater as suggested by 

 Meltzer. 



Laparotomy and duodenotomy was performed on several dogs 

 anesthetized with chloretone. Observation of the gall bladder 

 immediately after laparotomy showed a distended bladder in all 

 except one animal. The flaccid bladder was seen in a fasting dog. 



A solution of methylene blue was injected into the gall bladder 

 to differentiate its content from the bile flowing from the liver. 

 The duodenal mucosa in the region of and including the papilla 

 of Vater was irrigated with magnesium sulphate solution ; although 

 an increased flow of bile was observed, no expulsion of the gall 

 bladder content was noted. This observation was carried on for 

 several hours in a series of eight dogs. The gall bladder retained 

 its bile independent of whether the dog was in the fasting or the 

 actively digesting state. 



Stimulation of liver bile flow as obtained with magnesium 

 sulphate was also observed after the application of sodium sul- 

 phate, sodium phosphate, peptone, N/10 hydrochloric acid, bile 

 and sodium glycocholate. No stimulation was seen after the 

 application of water, sodium chloride or sodium hydroxide. 



