Figure 4.

WNK1 is critical for stimulation of TRPV4 activity by aldosterone in mpkCCD_c14 cells. (A) Representative pseudo-color images of [Ca²⁺]_i changes (blue—low and red—high) in confluent monolayers of mpkCCD_c14 cells treated with the selective WNK1 inhibitor WNK-in-11 (400 nM) in the absence and presence of concomitant administration of aldosterone at the baseline (1) and following 5 min application of TRPV4 agonist, GSK1016790A (2). (B) The averaged time-courses of [Ca²⁺]_i changes upon application of 40 nM GSK1016790A (shown with the bar on top) in individual WNK-in-11 pretreated cells mpkCCD_c14 cells in the absence and presence of aldosterone. The time-points 1 (baseline) and 2 (GSK1016790A) represent conditions shown in panel (A). (C) Summary graph comparing [Ca²⁺]_i values in individual WNK-in-11 pretreated mpkCCD_c14 cells in the control and following aldosterone treatment at the baseline and after GSK1016790A application. N.s. represents non-significant difference (p > 0.05).