Fig. 5.
Effect of membrane stretch on Iban-mediated inhibition of BKCa-channel activity in MDCK cells. Cells were bathed in high K+ solution containing 1.8 mM CaCl2. The experiments were conducted in cell-attached configuration with a holding potential of +30 mV. (A) Original current traces showing Iban-induced reduction of BKCa-channel activity obtained before (upper, black) and after (lower, blue) the membrane stretch induced by a negative pressure (−2 and −4 kPa). Upward deflections are the opening events of the channels. (B) Bar graph showing effects of negative pressure(−2 and −4 kPa) on BKCa channels in the absence (blue bars) and presence of 10 μM Iban (red bars). Values are means ± SEM for n = 7–10 cells in each group. *Significantly different from controls (P < 0.05). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)