THE BILE. 



177 



Fig. 46. 



the subjacent crystals show very distinctly through the substance 

 of those which are placed above. Cholesterin is not formed in the 

 liver, but originates in the 

 substance of the brain and 

 nervous tissue, from which 

 it may be extracted in large 

 quantity by the action of 

 alcohol. It has also been 

 found, by Dr. "W. Marcet, 1 to 

 exist, in considerable abund- 

 ance, in the tissue of the 

 spleen. From all these tis- 

 sues it is absorbed by the 

 blood, then conveyed to the 

 liver, and discharged with 

 the bile. 



CHOI. ESTER ix, from an Enrysted Tumor. 



This fact has been fully 

 confirmed by the researches 



of Prof. A. Flint, Jr., 7 who has found that there is nearly one-quarter 

 part more cholesterin in the blood of the jugular vein, returning 

 from the brain, than in that of the carotid artery, before its passage 

 through that organ ; and that, on the other hand, the blood of the 

 hepatic artery, as well as that of the portal vein, loses cholesterin 

 in passing through the liver, so that but a small quantity can be 

 found in the blood of the hepatic vein. 



The cholesterin, however, after being poured into the intestine 

 with the bile, is decomposed or transformed into some other sub- 

 stance, since it is not discharged with the feces. 3 Its decomposition 

 is probably effected by the contact of the intestinal fluids. 



BILIARY SALTS. By far the most important and characteristic 

 ingredients of this secretion are the two saline substances mentioned 

 above as the glylto-cholate and tauro-cholate of soda. These sub- 

 stances were first discovered by Strecker, in 1848, in the bile of the 

 ox. They are both freely soluble in water and in alcohol, but in- 

 soluble in ether. One of them, the tauro-cholate, has the property, 



1 In American Journ. Med. Sci., January, 155?. 



2 American Journ. Med. Sci., October, 1SG2. 



3 Prof. A. Flint, Jr., in Am. Journ. Med. Sci., Oct. 1862. 



12 



