FIGURE 3.

Effects of S1P and ATP concentration on the rate of ATP-dependent S1P transport into the IOVs. A, ATP-dependent S1P transport inside the IOVs was calculated from the different concentrations of [³³P]S1P in the presence or absence of 2 mm ATP at 37 °C for 5 min. B, different concentrations of ATP were used for ATP-dependent S1P transport. IOVs were incubated with 1 μm [³³P]S1P at 37 °C for 5 min. S1P uptake was expressed as the difference between the S1P amounts in the presence and absence of ATP. The inset shows the Lineweaver-Burk plot of the rate of ATP-dependent S1P uptake.