Cell contraction measured under control conditions, during drug treatment and during drug washout in ventricular myocytes from Wistar and DSS rats.

Cells were superfused with Tyrode solution containing OA, Me-OA and Br-OA (160 μmol L^-1) during the treatment period. Original tracings of cell shortening from Wistar (left panels) and DSS rats (right panels) are displayed in A (for OA), E (for Me-OA) and I (for Br-OA). Amplitudes of cell shortening (B, F and J), time to peak shortening (C, G and K) and time constant of relaxation (tau; D, H and L) were measured from Wistar (unfilled columns) and DSS rats (stripped columns) at 1 Hz stimulation frequency (n = 6) for each drug. C: control, OA: oleanolic acid, Me: methylated derivative, Br: brominated derivative, W: washout. * p < 0.001 for drug vs control (short horizontal bars), ** p < 0.0001 for Wistar vs DSS (long horizontal bars).