Figure 4.

Cav3‐F97C slows Ca²⁺‐dependent inactivation of Ca_v1.2 channels

A, representative I _Ba,L traces resulting from test pulses at 20 mV from HEK293 cells transfected with Ca_v1.2 + Ca_vβ_2cN4 and Cav3‐WT (n = 7), Cav3‐F97C (n = 9) or Cav3‐S141R (n = 7). Current decay of I _Ba,L was determined by measuring the ratio of the current present after 100 ms of a voltage step relative to the peak current (r100). B, representative I _Ca,L traces resulting from test pulses at 20 mV from HEK293 cells transfected with Ca_v1.2 + Ca_vβ_2cN4 and Cav3‐WT (n = 3), Cav3‐F97C (n = 5) or Cav3‐S141R (n = 5). Current decay of I _Ca,L was determined by measuring the ratio of the current present after 100 ms of a voltage step relative to the peak current (r100). C, the f value is plotted as an index of Ca²⁺‐dependent inactivation by eliminating the effect of VDI at test potentials from −20 to 20 mV, between Cav3‐WT (n = 3–7), Cav3‐F97C (n = 5–9) and Cav3‐S141R (n = 5–7), as described in the Methods.