Table 1

Kinetic parameters of rOat2-mediated uptake of salicylate, indomethacin, AZT, ddC, and PGE2

SubstratesKmVmax
μM pmol/min/mg of protein
Salicylate81.2  ± 19.01410  ± 210
IDM0.366  ± 0.06288.6  ± 6.9
AZT26.0  ± 1.366.3  ± 2.9
ddC3080  ± 5704020  ± 480
Prostaglandin E2 38.5  ± 10.5520  ± 87

The uptake of salicylate, IDM, AZT, ddC, and prostaglandin E2into rOat2-expressed LLC-PK1 cells was examined at different substrate concentrations. Kinetic parameters were obtained by fitting the Michaelis-Menten equation to the rOat2-mediated uptake velocity as described under Experimental Procedures.