enteroHepatic recycling depend on all of the following except:
a- Dosage form of the drug.
b- Extent of drug passed in feaces.
c- extent of drug absorption from stomach***
d- gall blader state.
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Enterohepatic circulation is the loop circulation of bile acids from the liver where they are produced and secreted into the bile, down to the small intestine where they allow the digestion of fats and other substances, with return to the liver.
Primary bile acids (cholic and chenodeoxycholic) from the bile acid pathway are conjugated in the liver with glycine or taurine to produce primary bile salts: glycocholate, glycochenate, taurocholate and taurochenate.
These salts are excreted in the bile towards the intestine. They are essential cofactors for the action of pancreatic lipase during the digestion of lipids, in the duodenum and the jejunum. In the ileum, under the action of intestinal bacteria, the bile salts are deconjugated. Cholic acid is partially converted to deoxycholic acid (3α, 12α dihydroxy) and chene acid to lithocholic acid (3α hydroxy). Deoxycholic and lithocholic are secondary bile acids.
Primary and secondary bile acids are reabsorbed in the ileum and transported through the portal vein to the liver. A small portion of these bile acids pass through the liver and are excreted in the urine. All bile acids recaptured by the liver are reconjugated as the primary bile acids, except the lithocholic which is sulfoconjugate or reoxidized in ursodeoxycholate, tertiary bile acid. The resulting primary and secondary bile salts are excreted again in the bile: this metabolic pathway is the enterohepatic cycle of bile salts.
In the intestine, the deconjugated primary and secondary bile acids are also excreted in the feces. Sulfolithocholate is neither deconjugated nor reabsorbed, so it must be excreted.
Bile acids are the products of the catabolism of cholesterol. The cholesterol itself and the bile acids are excreted in the bile towards the intestine; all are strongly reabsorbed but a small part is eliminated in the feces, in quantity as important as the intake of dietary and endogenous cholesterol (synthesis).
His first description, in 1868, was given to the German physiologist Moritz Schiff, who left him his name (Schiff's Biliary Cycle).
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Enterohepatic circulation is the loop circulation of bile acids from the liver where they are produced and secreted into the bile, down to the small intestine where they allow the digestion of fats and other substances, with return to the liver.
Primary bile acids (cholic and chenodeoxycholic) from the bile acid pathway are conjugated in the liver with glycine or taurine to produce primary bile salts: glycocholate, glycochenate, taurocholate and taurochenate.
These salts are excreted in the bile towards the intestine. They are essential cofactors for the action of pancreatic lipase during the digestion of lipids, in the duodenum and the jejunum. In the ileum, under the action of intestinal bacteria, the bile salts are deconjugated. Cholic acid is partially converted to deoxycholic acid (3α, 12α dihydroxy) and chene acid to lithocholic acid (3α hydroxy). Deoxycholic and lithocholic are secondary bile acids.
Primary and secondary bile acids are reabsorbed in the ileum and transported through the portal vein to the liver. A small portion of these bile acids pass through the liver and are excreted in the urine. All bile acids recaptured by the liver are reconjugated as the primary bile acids, except the lithocholic which is sulfoconjugate or reoxidized in ursodeoxycholate, tertiary bile acid. The resulting primary and secondary bile salts are excreted again in the bile: this metabolic pathway is the enterohepatic cycle of bile salts.
In the intestine, the deconjugated primary and secondary bile acids are also excreted in the feces. Sulfolithocholate is neither deconjugated nor reabsorbed, so it must be excreted.
Bile acids are the products of the catabolism of cholesterol. The cholesterol itself and the bile acids are excreted in the bile towards the intestine; all are strongly reabsorbed but a small part is eliminated in the feces, in quantity as important as the intake of dietary and endogenous cholesterol (synthesis).
His first description, in 1868, was given to the German physiologist Moritz Schiff, who left him his name (Schiff's Biliary Cycle).
