1. From: Selective Hcn1 Channels Inhibition by Ivabradine in Mouse Rod Photoreceptors
Invest. Ophthalmol. Vis. Sci ;50(4): doi: /iovs
Figure Legend:
Selective inhibition of I h by ivabradine. (A, B) Outward currents were generated in response to 800-ms long voltage-steps, ranging from −70 to +50 mV, from a holding voltage of −80 mV. The step duration was selected to attain steady state deactivation of the transient outward current. Data in (A) and (B) plot currents recorded in response to voltage stimuli ranging from −10 to +50 mV in 20-mV steps before (thin traces) and after (thick traces) application of 30 μM ivabradine (A) or 3 mM CsCl (B). Horizontal dashed lines indicate zero-current levels. (C, D) Data points plot average difference-record amplitudes from three independent experiments using 30 μM ivabradine (C) or 3 mM CsCl (D). Currents were measured at the end of the 0.8-second long voltage steps stimuli, ranging from −50 to +50 mV in 10-mV steps. (E) Sweeps plot currents generated in response to voltage-clamp stimuli ranging from −30 to +50 mV in 20-mV steps. Large inward tail currents were measured on stepping back to −35 mV from +10 (∗) and +30 mV (∗∗) steps, indicating that the outward current is carried in part by chloride, whose reversal potential is close to zero. No inward tail was measured after stepping back from +50 mV. Note that this chloride current was erratic, was expressed by a fraction of rods, and may in addition spontaneously appear and fade out during recording in the absence of ivabradine. (F) Sweeps plot current generated in response to voltage stimuli ranging from −30 to +30 mV in 20-mV steps before (thin traces) and after (thick traces) I h inhibition by 30 mM ivabradine (note the differences in the holding currents at −90 mV). *Records in ivabradine.
Date of download: 10/26/2017
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