Figure 1.

Hesperetin (HSP) barely affects the electrical and contractile activities of isolated hearts and the contraction of aortic rings. Dot and line plots of the effect of hesperetin (HSP) on the (a) QRS duration, (b) corrected QT (QTc), and (c) RR intervals. Hesperetin (100 μmol·L⁻¹) significantly changed the QTc and RR; the QRS was significantly affected by the two higher concentrations of hesperetin studied (N = 5, *P < 0.05, one‐way repeated measures ANOVA with Tukey's post hoc test). (d) Example recordings of ECG (upper panel) and force of contraction (lower panel) in control condition and under the action of hesperetin (100 μmol·L⁻¹). Hesperetin had a significant inhibitory effect on the force of contraction at 100 μmol·L⁻¹ (N = 5, P < 0.05, one‐way repeated measures ANOVA with Tukey's post hoc test). (e,f) Representative recordings of the effects of different concentrations of hesperetin (in μmol·L⁻¹) on aortic ring contraction induced by 60 mmol·L⁻¹ KCl or by 10 μmol·L⁻¹ phenylephrine (PE)