{"id":87,"date":"2019-04-24T12:15:55","date_gmt":"2019-04-24T12:15:55","guid":{"rendered":"https:\/\/sepia2.unil.ch\/pharmacology\/?page_id=87"},"modified":"2019-04-26T14:22:46","modified_gmt":"2019-04-26T14:22:46","slug":"biliary-excretion","status":"publish","type":"page","link":"https:\/\/sepia2.unil.ch\/pharmacology\/mechanisms\/biliary-excretion\/","title":{"rendered":"Biliary Excretion"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\"> &#8220;Irreversible transfer of drug or drug metabolites from the plasma to  the bile through the hepatocytes (biliary excretion). This can be  followed by intestinal reabsorption of the active drug (enterohepatic  cycle)&#8221; <\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Description<\/h3>\n\n\n\n<div class=\"wp-block-columns has-2-columns is-layout-flex wp-container-core-columns-is-layout-9d6595d7 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p>Drugs are transferred from the plasma into the bile \nthrough the hepatocytes. This transport is due to active secretion of \ndrugs into the bile by means of transport systems: e.g. the organic \nanion transporting polypeptides (OATPs), the P-glycoprotein transport \nsystem and the multidrug resistance-associated proteins (Mrps). The \nlatter are important for the excretion of conjugated metabolites. \n<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-video\"><video height=\"346\" style=\"aspect-ratio: 346 \/ 346;\" width=\"346\" controls src=\"https:\/\/sepia2.unil.ch\/pharmacology\/wp-content\/uploads\/2019\/04\/biliaryexcretion_Trim.mp4\"><\/video><\/figure>\n<\/div>\n<\/div>\n\n\n\n<p>Drug in bile enters the gastrointestinal tract after\n storage in the gallbladder. It may then be excreted from the body by \nthe stools.\n<\/p>\n\n\n\n<p>Drugs may be excreted into the bile either in a native form or after <a href=\"\/pharmacology\/metabolism\">metabolism<\/a>\n into more polar conjugates. The bile is released in the gut lumen, from\n which the native drug can be reabsorbed. In the small intestine, the \nenzymes of the intestinal flora may hydrolyze the conjugated metabolites\n and free the active drug, which may in turn also be reabsorbed. After \npenetrating the intestinal mucosa, the active drug enters the portal \nvein, which carries it back to the liver. This cycle is called the \nenterohepatic cycle and may be repeated several times, significantly \nprolonging the body exposure to the drug.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Clinical implications<\/h3>\n\n\n\n<p>Biliary excretion can be inhibited due to \ndisorders such as hepatic or gallbladder diseases. Transporter-mediated \nsecretion of a drug into the bile may be competitively inhibited by \nother drugs or endogenous substances. In such conditions, <a href=\"\/pharmacology\/clearance\">clearance<\/a> of the drug may be reduced and the <a href=\"\/pharmacology\/dosage-regimen\">dosage regimen<\/a> must be adapted.\n<\/p>\n\n\n\n<p>Drugs undergoing enterohepatic cycling have a prolonged <a href=\"\/pharmacology\/halflife\">half-life<\/a> and the <a href=\"\/pharmacology\/repeated-administration\">dosing interval<\/a> should thus be prolonged accordingly. <\/p>\n","protected":false},"excerpt":{"rendered":"<p>&#8220;Irreversible transfer of drug or drug metabolites from the plasma to the bile through the hepatocytes (biliary excretion). This can be followed by intestinal reabsorption of the active drug (enterohepatic cycle)&#8221; Description Drugs are transferred from the plasma into the bile through the hepatocytes. This transport is due to active secretion of drugs into the &hellip; <\/p>\n<p class=\"link-more\"><a href=\"https:\/\/sepia2.unil.ch\/pharmacology\/mechanisms\/biliary-excretion\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Biliary Excretion&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":11,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-87","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/sepia2.unil.ch\/pharmacology\/wp-json\/wp\/v2\/pages\/87","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sepia2.unil.ch\/pharmacology\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/sepia2.unil.ch\/pharmacology\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/sepia2.unil.ch\/pharmacology\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/sepia2.unil.ch\/pharmacology\/wp-json\/wp\/v2\/comments?post=87"}],"version-history":[{"count":2,"href":"https:\/\/sepia2.unil.ch\/pharmacology\/wp-json\/wp\/v2\/pages\/87\/revisions"}],"predecessor-version":[{"id":311,"href":"https:\/\/sepia2.unil.ch\/pharmacology\/wp-json\/wp\/v2\/pages\/87\/revisions\/311"}],"up":[{"embeddable":true,"href":"https:\/\/sepia2.unil.ch\/pharmacology\/wp-json\/wp\/v2\/pages\/11"}],"wp:attachment":[{"href":"https:\/\/sepia2.unil.ch\/pharmacology\/wp-json\/wp\/v2\/media?parent=87"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}