Figure 1.
Proton-elicited responses in cultured SG neurons. A, Inward currents elicited by increasing concentrations of protons. The pH values and approximate duration of the application of external solutions to the cell are indicated by the numbers and horizontal bars above the data trace, respectively. Normal external solution was perfused between the proton applications. The currents were recorded from an SG neuron voltage clamped at -70 mV. B, Dose-response curve of the normalized peak current. The data were fitted with a smooth curve using the following equation: %response = 100 × [pH]n/([pH]50n + [pH]n), in which [pH]50 is the pH value at which half-maximal currents was obtained, and n is the coefficient factor. Black dots and error bars give the average data and SEMs, respectively. C, Action potentials elicited by increasing concentration of protons in an SG neuron. The approximate duration of the application of the pH 6.8 solution is indicated by a horizontal bar underneath the data trace. The neuron was current clamped at its resting membrane potential of -65mV; therefore, no DC was injected.