Figure 3. Effect of the dihydropyridine compound nifedipine on voltage-dependent Ba²⁺ currents of freshly isolated RPE cells

A: Ba²⁺ currents induced by a 50 ms voltage-step from -70 mV to +10 mV in a retinal pigment epithelium (RPE) cell freshly isolated from an eye without choroidal neovascularization (CNV) under control conditions and in the presence of nifedipine (10^-5 M). B: Curves of voltage-dependent activation from six freshly isolated cells from eyes without CNV: three cells under control conditions and three cells in the presence of nifedipine. Currents were normalized to the maximal current amplitude and fitted using the Boltzmann equation. C: Ba²⁺ currents induced by a 50 ms voltage-step from -70 mV to +10 mV in an RPE cell freshly isolated from a CNV membrane under control conditions and in the presence of nifedipine (10^-5 M). D: Curves of voltage-dependent activation from eight cells freshly isolated from CNV membranes: six cells under control conditions and two cells in the presence of nifedipine. Currents were normalized to the maximal current amplitude and fitted using the Boltzmann equation. E: Comparison of the inhibitory effect of nifedipine in freshly isolated RPE cells from eyes without CNV and from CNV tissues. Maximal currents at +10 mV under control conditions were set as 100%.