family of OATP family OATPS family (canonical)[Cholestasis] SLCO1B3 (canonical)[Cholestasis] OATP1B3 The sodium-independent portion of bile salt uptake is mediated by OATPs (organic anion transporting polypeptides). OATP1B1 (SLCO1B1), OATP1B3 (SLCO1B3), and OATP2B1 (SLCO2B1) are expressed at the basolateral plasma membrane of hepatocytes, although OATP2B1 appears not to be a bile Salt transporter.