Contractile properties from fresh and frozen porcine myocardium. (A) Skinned myocyte force–calcium relationships from porcine left ventricular myocardium either isolated immediately after sacrificing the animal or flash-frozen and subsequently isolated. Both fresh and frozen cells were isolated from the same three pigs from tissue samples immediately adjacent to each other. (B and C) Summary Fmax (B) and EC50 (C) data corresponding to the force–calcium graph in A. (D) Cross-sectional area (CSA) was calculated from each cell assuming an elliptical cross-section, with no difference between the groups. (E) Passive tension at sarcomere length of 2.1 μm was also not different between the fresh and previously frozen myocytes. Solid, open, and half open/closed symbols are from different biological repeats. ns: P ≥ 0.05. The error bars in the graphs are SEM.