Figure 2. Cl⁻ currents in isolated Xenopus RPE cells.

Standard extracellular and intracellular solutions are described in Methods. Cells were voltage clamped in whole-cell mode. Holding potential was −20 mV. Upper left: voltage clamp protocol. A, traces recorded from a cell with the pipette solution containing < 20 nm free Ca²⁺. B, traces recorded from a cell with the pipette solution containing 10 μm free Ca²⁺. C, average steady-state current-voltage relationships for cells with < 20 nm Ca²⁺ (○, n = 12) or 10 μm free Ca²⁺ (▪, n = 9).