Figure 5.

Calcium handling profile

(A) Representative confocal images of non-patterned and rod-shaped CMs loaded with Fluo-4-AM Ca indicator.

(B and C) Representative recordings of field stimulation-induced calcium transient (1 Hz) in non-patterned (B) and rod-shaped hiPSC-CMs (C) and their corresponding fluorescence map.

(D) Violin plot showing beating rates from non-patterned and rod-shaped hiPSC-CMs, stimulated at 1 Hz.

(E) Representative superimposed calcium recording traces from non-patterned and rod-shaped hiPSC-CMs.

(F–L) Violin plots of (F) calcium transient amplitude, (G) calcium transient area under the curve, (H) time to peak, (I) maximum rising rate, (J) maximum decay rate, (K) time to 90% relaxation, and (L) peak to 10% decay time.

(M) RNA expression of ATP2A2, PLN, CASQ2, and RYR2 measured by SYBR green in non-patterned and rod-shaped hiPSC-CMs. Cts were normalized to RPL32, and the ratio of rod-shaped vs. non-patterned was calculated for each cardiac differentiation. For (D–K), n = 100–175 cells from 3 independent experiments. Adjusted linear mixed models: ns p > 0.05, ^∗∗p < 0.01 vs. non-patterned hiPSC-CMs. For (M), n = 3 independent experiments of 7 differentiations per condition. Mann-Whitney: ns, p > 0.05 vs. non-patterned hiPSC-CMs.