Fig. 4: Ultrasound and pressure generate membrane tension to activate TRAAK channels.
From: Tension activation of mechanosensitive two-pore domain K+ channels TRAAK, TREK-1, and TREK-2
A Overlaid macroscopic currents (left) and corresponding fluorescent images (right) from a TRAAK-containing patch in response to pressure (periwinkle) and ultrasound (green) stimulation. Traces and images are compared from the same patch activated to high (upper) and moderate (lower) I/Imax. Circle fits (red) and corresponding membrane radii of curvature are indicated on the images. Similar patch radii are observed when ultrasound or pressure stimuli generate similar channel activation. B Normalized current-patch radius relationship calculated from a single patch in response to ultrasound and pressure stimulation. C Comparison of patch radius generated by pairs of stimuli (with pressure preceding ultrasound) that give comparable channel activation in the same patch. Data from nine paired recordings from five different patches are shown (p = 0.18, two-tailed paired t-test, not significant).
