Fig. 7.

A Maximal active tension in response to alterations in pCa for triton skinned RV myocytes from CON and FAIL hearts. Experiments were performed at 25 °C. Data was collected at SL 2.0 and 2.3 μm and fitted to a Hill equation. Increased SL caused a left shift in the curves. B Change in the pCa50 (index of length-dependent increase in myofilament Ca²⁺- sensitivity) in response to an increase in SL from 2.0 to 2.3 μm for RV and LV myocytes from CON and FAIL hearts. There was a significant difference in ΔpCa50 between RV and LV in CON myocytes but no differences between CON and FAIL (CON RV n = 12; CON LV n = 12; FAIL RV n = 18; FAIL LV n = 14 from N = CON 3, FAIL 4 hearts). *P < 0.05.