Figure 1. Effect of ATP concentration on the volume-sensitive anion conductance in swollen rat β-cells.

Aa, typical current profiles with different concentrations of intracellular Mg²⁺-ATP. Cells were held at -30 mV and subjected to 500 ms voltage pulses from -100 to +100 mV. The pipette solutions were maintained at constant hypertonicity (305 mosmol l⁻¹) in order to induce cell swelling. Ab, current-voltage (I-V) plot for a typical cell dialysed with a pipette solution containing 2 mM ATP. The reversal potential for this cell was -31 mV. B, outward (I₊₁₀₀) and inward (I_-100) current densities in response to voltage pulses of +100 and -100 mV, respectively: effects of increasing concentrations of Mg²⁺-ATP. All values represent maximum currents attained in each cell. The values in parentheses represent the number of cells for each treatment. *P < 0.05, **P < 0.01 between the groups as shown; n.s., P > 0.05.