Figure 7
From: Estrogen ameliorates microglial activation by inhibiting the Kir2.1 inward-rectifier K+ channel
Inhibitory effect of 17β-estradiol (E2) on the activity of inwardly rectifying K+ channel 2.1 recorded from BV2 microglia.
(a) In this set of experiments, the cells were held at −50 mV and various potentials ranging from −120 to +10 mV in 10-mV increments were applied (upper panel). Original current traces obtained from cells in the absence (Control) and presence of E2. (b) Average current-voltage (I-V) relations of IK(IR) in the absence (blue circles) and presence (red circles) of E2 (n = 5–9). * (p < 0.05): versus controls measured at the same level of voltage. Adding E2 significantly suppressed the IK(IR) amplitude measured at the voltage ranging between −90 and −120 mV. (c) Original single-channel currents obtained in the absence (black trace) and presence (blue trace) of 3 μM of E2. The attached cell was held at 0 mV relative to the bath. Channel opening gives a downward deflection in current. The boxed regions are enlarged and shown beneath the original trace. (d) Summary of the data showing the dose-dependent effect of E2 on the probability of the Kir channel opening (n = 9–10). * (p < 0.05): versus Controls measured at the same level of voltage. Each cell was held at 0 mV.
