Characterization of a voltage-gated K+ channel that accelerates the rod response to dim light.

摘要: Abstract In this study a K + current, I Kx , in isolated salamander rod photoreceptors was characterized and its role shaping small photovoltages examined. is standing outward current of about 40 pA at −30 mV that deactivates slowly when the cell hyperpolarized ( τ max = 0.25 s). The voltage time dependence are similar to M-current, but can be distinguished from M-current because it not suppressed by acetylcholine "blocked" external Ba 2+ surprising manner: activation range shifted strongly positive direction. Using current-clamp recordings computer simulation photo-response, we show figures prominently setting dark resting potential accelerates response photocurrents.