Fig. 4

Cardiomyocyte contractile and intracellular Ca²⁺ properties from area-at-risk from WT and BECN^+/− mouse hearts following MI with or without MSCs transplantation. a Light microscopic images of freshly isolated cardiomyocytes: b Resting cell length; c Peak shortening (normalized to resting cell length); d Maximal velocity of shortening (+ dL/dt); e Maximal velocity of relengthening (− dL/dt); f Time-to-peak shortening (TPS); g Time-to-90% relengthening (TR₉₀); h Baseline intracellular Ca²⁺ fura-2 fluorescence intensity (FFI); i Electrically-stimulated increase in fura-2 fluorescence intensity (ΔFFI); and j Intracellular Ca²⁺ transient decay rate. Mean ± SEM, n = 15 cardiomyocytes per group, * p < 0.05 between indicated groups