Figure 5. Concentration-dependent inhibition of the csNSC currents by protons.

Currents were activated by a step decrease of [Ca²⁺]₀ from 2.0 to 0.2 mM at the holding potential of −60 mV. A, representative traces taken from the same neuron demonstrate that the csNSC currents are inhibited by protons in a concentration-dependent manner. B, summary data showing the concentration-dependent effect of protons on the csNSC current. The mean IC₅₀ for proton inhibition of the csNSC current is pH 6.2 ± 0.3 (n = 4).