Figure 1.

Tcap KO is associated with progressive Ca²⁺ transient defects. (A) The figure shows line scans of stimulated ventricular cardiomyocytes from 3 months old or 8 months old WT and Tcap KO hearts. The colour chart is a normalized scale of fluorescence intensity (a marker of Ca²⁺ concentration). 3mWT n = 40, 3mKO n = 48, 8mWT n = 48, 8mKO n = 43. The vertical scale bar represents 100 pixels and the horizontal scale bar represents 100 ms. Variance of time to peak (B), amplitude (C) and time for 50% (D) and 90% (E) decline and the time to peak (F) of the Ca²⁺ transient were deleteriously affected in the KO. Importantly, the variance of the time to peak (which is closely associated with changes to the t-tubules) was the only parameter influenced at 3 m.