Fig. 3.
Long-term exposure to extracellular 0.1–10 μM curcumin modulates IClswell. IClswell was activated in human renal cells (HEK293 Phoenix) by hypotonic shock and measured by the patch clamp technique in whole cell configuration. Current density-to-voltage relations measured in extracellular hypertonic solution (hyper), and after a 30 min exposure to an extracellular hypotonic solution (30 min hypo) in cells incubated 15–23 h in a complete medium containing (a) 0.1, (c) 0.5, (e) 1.0, (g) 5.0, (i) and 10 μM curcumin or 0.05% DMSO. Data were fitted with second order polynomials (dotted lines), following application of the extra-sum of squares F test, and showed that 0.1 μM curcumin had no effect, 0.5–5.0 μM improved and 10 μM impaired the activation of IClswell. The respective current density-to-time relations (b, d, f, h and k) measured in extracellular hypotonic solution showed similar results.