Fig. 4.

DHE and hortiamine prolong the FPD (A) Averaged traces on the left represent the independent, time matched, DMSO control field potential. The percent change in beat period (BP), field potential duration (FPD), and depolarisation spike amplitude (AMP) for five consecutive recordings is shown on the right. Control 1 combines the controls of the two MEAs treated with DHE, and control 2 – the control wells on the two chips treated with hortiamine. (B) The representative, averaged traces on the left visualise the shift of the t-wave and the prolongation of the FPD following treatment with DHE: blue (baseline), yellow (0.01 µM), black (0.03 µM), red (0.1 µM), and purple (0.3 µM). The relative changes in BP, FPD, and AMP, compared to baseline are shown on the right (n = 10). One-sample t-test was used, n.s. p > 0.05, *p < 0.05, **p < 0.01, ***p < 0.001. (C) The representative traces on the left visualise the FPD following treatment with hortiamine. The percent changes to the three parameters (BP, FPD, AMP) are shown on the right (n = 10). One-sample t-test was used. See Supplementary Table 15 S for the beat rate corrected field potential duration (FPDc).