Transactivation of the Human 0atp8 Gene By the Farnesoid X Receptor/ Bile Acid Receptor (fxr/bar)

摘要

The role of the organic anion transporting polypeptides (OATPs) as multispecific transport proteins that are expressed at the plasma membrane of diverse epithelial cell types has been elucidated in recent years. Hepatocytes express several representatives of the OATP family at the basolateral membrane (Fig. 1). In human hepatocytes nearly all known OATPs are expressed to some degree, although the highest expression levels have been found for OATP-B (SLC21A9), OATP-C (also called OATP2, SLC21A6) and OATP8 (SLC21A8). Whereas OATP-B appears to possess a limited substrate specificity (substrates include bromo-sulphophthalein and sulphated* sex steroids), OATP-C is an efficient transport system for organic anions including bile salts. OATP8 exhibits a broad substrate specificity that includes organic anions, xenobiotics (digoxin) and selected oligopeptides such as opioid peptides and cholecystokinin.