Fig. 1. Effects of carbon monoxide (CO) on large-conductance Ca2+-activated K+ currents of HCFs.
(A) Original recordings of K+ outward currents were obtained by repeated voltage step depolarization from −80 to +50 mV for 400 ms (holding potential, –80 mV) before (control) and after the application of CO-releasing molecules (CORMs; CORM-2 or CORM-3, 10 μM, each) in whole-cell mode patch-clamp recordings. Paxilline (10 μM) was added to confirm IBK. (B) Summarized current–voltage (I–V) curves for the effects of CO donors and paxilline show a strong outward rectification that characterizes IBK. Values are mean ± SEM. **p < 0.01, ***p < 0.001 compared to control (n = 10, each). (C) Bar graphs showing the summary of the current density changes at +50 mV regarding the effects of CORM-2, CORM-3, and paxilline (n = 10, each). (D) Concentration-dependent activation curves of IBK by CORM-2 and CORM-3 are shown. The solid line shows the fit based on a standard dose-response relationship, which yielded an estimated half maximal effective concentration (EC50) of 9.8 μM for CORM-2 and 10.9 μM for CORM-3.
© Korean J Physiol Pharmacol
