FIGURE 2.

Steady-state activity of PC2 channels is greater with reduced Ca²⁺ buffering (0.1 mM BAPTA compared to 2 mM BAPTA). (A) Steady-state activity was measured in one cilium at the voltages shown in 0.1 mM BAPTA (left) and 2 mM BAPTA (right). (B) In a cilium with just one PC2 channel, the channel also showed higher steady-state activity with the lower concentration of BAPTA. (C) The effect of reduced Ca²⁺ buffering is reversible. A cilium with a single PC2 channel showed higher steady-state activity in 0.1 mM BAPTA before and after exposure to 2 mM BAPTA. Voltage was maintained at 0 mV. (D) Paired mean steady-state currents for 13 cilia, each tested in both 0.1 and 2 mM BAPTA. Voltages were chosen that gave the greatest difference in mean current between 0.1 and 2 mM BAPTA and ranged from −20 to +80 mV *p < 0.001. (E) Steady-state currents in the one cilium in which activity increased with hyperpolarization in the presence of 0.1 mM BAPTA.