Figure 4.

H₂S Donors Potentiate Endogenous ASIC Currents in Cultured Mouse Hypothalamus Neurons. The currents were measured by whole-cell voltage-clamp at −60 mV from cultured hypothalamus neurons of mice. The bars and error bars indicate mean±SEM. Together with each treatment condition, a number of control cells (ie, treatment protocol with solution lacking the H₂S donor) were measured, and the current amplitudes obtained for the treatment and for the respective control were normalized to the average of the control. (A and B) Cells were exposed for 1 min to NaHS and then put back into the incubator for a defined period before the current measurement. (A) pH 6.6-induced current amplitudes measured 1 h after exposure to the indicated NaHS concentration (treatment, blue) or to control solution without NaHS (control, black), n = 5–8. B, pH 6.6-induced current amplitudes measured at the indicated time after a 1-min 100 µM NaHS (blue symbols) or control exposure (black symbols), n = 6–9. (C and D) The H₂S donor GYY4137 at the indicated final concentrations was added to the culture medium, and cells were incubated in the cell incubator for the indicated period. (C) pH 6.6-induced current amplitudes measured after 1 h incubation with the indicated concentration of GYY4137 (treatment, blue) or with the addition of solution lacking GYY4137 (control, black), n = 7–9. (D) pH 6.6-induced current amplitudes measured after incubation for the indicated time with 10 µM GYY4137 (treatment, blue) or with solution lacking GYY4137 (control, black), n = 8–10. *P < 0.05; **P < 0.01; ***P < 0.001; comparison of each treatment condition with the corresponding control condition by unpaired multiple Mann–Whitney tests.