The mechanism of the precipitation of cholesterol from bile to form gallstones has received increasing attention in recent years. Since the solubility of cholesterol in bile is dependent, to a great extent, on the presence of bile salts, considerable investigation has been directed toward the bile salt-cholesterol ratio in gallbladder bile. Experimental work on dogs clearly demonstrated that the wall of the inflamed gallbladder absorbs the bile salts of the contents rapidly, leaving an increased concentration of cholesterol.1 A large number of studies of bile removed from the gallbladder either at operation1 or at autopsy2 in cases of disease of the bladder indicated that with the increasing inflammation of the organ the bile salt—cholesterol ratio was progressively lowered. This lowered ratio was obviously due to the decreased concentration of bile salts.
The methods employed by these various investigators for the determination of bile salts were either the Gregory-Pascoe