| MadSci Network: Anatomy |
Lipophilic compounds that are absorbed in the intestine, excreted in the bile, reabsorbed in the intestine, and returned to the liver, where bile is made, reexcreted in the bile, and reabsorbed in the intestine is said to have accomplished enterohepatic circulation. Enterohepatic circulation serves as an efficient physiological mechanism for the conservation of bile salts and certain hormones. However, when xenobiotics are caught up in this cycle, their biological half-lives and effects on the liver may be significantly increased. Bile acids are necessary for the absorbtion of lipids when ingested and present in the small intestine. When one ingests a meal, hormonal secretions cause the gallbladder to release bile for this lipid metabolism.
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