Figure 6.

Ca_v3.2(H191C) is ascorbate-insensitive, but Cu²⁺-sensitive. A, Raw traces showing the lack of ascorbate effect on Ca_v3.2(H191C) currents in an HEK293 cell. Similar results were obtained in experiments from five additional cells (peak current in the presence of ascorbate was 96.2 ± 1.2% of control). B, Concentration–response curve for inhibition of Ca_v3.2(H191C) by Cu²⁺. Average data were fit with Equation 1 to generate the curve: IC₅₀, 1.07 ± 0.16 μm; h, 0.79 ± 0.09 (n = 4–7). The dotted line represents Ca_v3.2 data recorded under nearly identical conditions (HEK293 cells, 10 mm Ba²⁺) (Jeong et al., 2003).