Choleresis

Choleresis, the excretion of bile by liver cells, represents simultaneously secretion (of bile acids) and excretion (of bilirubin, foreign substances, for example dyes and the like). The term X. was introduced by Brugsch for contrasting the bile-secreting function of the liver with bile excretion (cholekinesis). X. proceeds continuously (which indicates its excretory nature), intensifying during digestion. Regulation of X. during digestion coincides with regulation of pancreatic secretion. X. intensifies upon entry of acidic chyme into the duodenum or in experiment with hydrochloric acid (0.4%), reaching maximum strength 3 hours after food intake and then rapidly diminishing. Complete severance of the nerve pathways connecting the liver with the central nervous system does not affect X. Intravenous administration of secretin enhances X., as does pancreatic secretion. Among food substances, fats have the greatest stimulating effect on X. Bile acids and their salts (decholine-sodium dehydrocholate, Natr. cholalicum), butyric acid, salicylic acid, and magnesium sulfate possess marked choleresis effects. Enhancement of X. manifests in an increase in the total amount of bile per unit time and in an increase in its concentration. True enhancement of X. should be distinguished from apparent increase, in which the excretion of water with bile increases, but the excretion of other ingredients decreases. Such false enhancement of X. is caused by atophan, which damages liver cells. Substances that suppress X. include pituitrin.