PRODUCTION OF FAT AND SUGAR. 207 







the bile-ducts. The contradictory statements whicii have been made by 

 the most eminent anatomists respecting the connection of the bile-ducts 

 and the bile-cells some believing that the bile-ducts are covered inte- 

 riorly with the cells ; others, that the ducts end on the outside of the 

 lobules ; others, that the passages reported to have been seen among the 

 cells are interstitial channels and not proper vessels make it just as 

 probable, anatomically, that the cells belong to the hepatic veins as that 

 they belong to the biliary ducts. 



It is true that there may be a mixed action, and that presence of bil- 

 iary matter may be necessary to the sugar and fat producing agency. 

 This interworking and mutual dependency of functions is not without a 

 parallel. Thus the lung, viewed as a secreting or excreting gland, has 

 for its object the removal of carbonic acid from the system ; but it also 

 discharges another duty, which is dependent for its accomplishment 

 upon the physical or chemical qualities of the hsematin of venous blood, 

 the introduction of oxygen by aerating or arterializing. But the excre- 

 tion of carbonic acid and the introduction of oxygen, though separate 

 physiological events, and to be spoken of as distinct functions of the 

 lung, are yet nevertheless interconnected ; the one is essential for the ac- 

 complishment of the other, and the one effect is made the means by 

 which the other is brought about. 



So it may be in the liver: the contact of bile with the secreting cells 

 may be essential to their sugar or fat producing action. 



The deposit of fat and the production of bile seem to be inversely as 

 each other. Bidder and Schmidt found that fat animals Relation of the 

 yield less bile than lean ones, and that when they were fed 

 on fat the quantity was smaller than in the case of animals of bile, 

 fed on a less fatty diet. From such facts, the inference has been drawn 

 that the accumulation of fat is in consequence of a diminution of the se- 

 cretion of bile, and not that the diminution is the consequence of the an- 

 imal being fat. In such discussions it should, however, be recollected, 

 that the fats do not furnish all the substances required for the produc- 

 tion of bile, but only a limited portion thereof. Thus there are reasons 

 for the belief that sugar, lactic acid, or some other allied body is essen- 

 tial to that process, and it is very clear that so too are the materials 

 furnished from the decay of the cells of the blood. 



With respect to the production of sugar in the liver, it may be re- 

 marked, that the quantity of that substance in the solid res- p roduction of 

 idue of the serum of hepatic blood is from ten to sixteen sugar and fat 

 times greater than in the same residue from the portal blood ; 1] 



id in animals undergoing starvation, though no sugar could be found in 



>rtal blood, it occurred to such an extent in the corresponding hepatic 



lous blood, that Lehmann found that its quantity could be determined 



