In this study, we have elucidated that propionate, one of the short chain fatty acids (SCFAs), is the transport substrate for murine organic anion transporter 2 (mOat2), which is expressed in the kidneys and the liver. When expressed in Xenopus oocytes, mOat2-mediated [(3)H]PGE(2) transport was inhibited by three- to five-carbon SCFAs (C3 to C5). Among the SCFAs tested, propionate (3-carbon SCFA) was transported by mOat2 in a time-dependent manner. Since propionate is a potent glucogenic compound, Oat2 may be involved in the regulation of cellular metabolism through the transport of these metabolites in the kidneys and the liver.