On the basolateral side of the plasma membrane, cephaloridine (CED) is taken into tubule cells by the organic anion transporters 1, 2, and 3 (OAT 1, 2, 3) whereas OAT4 and the organic cation/carnitine transporter 2 (OCTN2) mediate uptake on the apical side. Efflux transporters for cephaloridine are largely unknown and may involve multidrug and toxin extrusion protein 1 and 2-K (MATE1/2-K).