Ageing Increases Cardiac Electrical Remodelling in Rats and Mice via NOX4/ROS/CaMKII-Mediated Calcium Signalling

Figure 3

Optical mapping showed that ageing modulated AP and calcium duration. (a, b) The typical APD₈₀ map and AP trace (young: black line; old: red line) in intact Langendorff perfused young and old mouse hearts before and following 1 μM ISO challenge in pacing at 10 Hz. (c) Quantitative analysis of APD₈₀ from individual hearts in young and old mice before and following 1 μM ISO (, , and ). (d) Ageing induced fractional increases in APD₈₀ challenged by ISO (ΔAPD₈₀) (). (e) The typical CV map. (f) Quantitative analysis of APD₈₀ from individual hearts in young and old mice before and following 1 μM ISO (). (g, h) The typical CaTD₅₀ map and calcium transient trace (young: black line; old: red line) in intact Langendorff perfused young and old mouse hearts before and following 1 μM ISO challenge in pacing at 10 Hz. (i) Quantitative analysis of CaTD₅₀ from individual hearts in young and old mice before and following 1 μM ISO , , and ). (j) Ageing induced fractional changes in APD₈₀ challenged by ISO (ΔCaTD₅₀) (). (k) The representative CaTD map shows the calculation of decay constant () by fitting of exponential decay points between 30% and 90% decay from the peak (_–90), illustrated for the regional signal in red. (l) Histogram showing the _–90 in young and old mice before and following 1 μM ISO pacing at 10 Hz ( and ). (each group).

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