Figure 8.

Direct determination of calcium-activated force generation in single adult cardiac myocytes. (a) Fast time-base records of isometric tension for a single control cardiac myocyte (records a–f) and a single cardiac myocyte after AdCMVR92Q gene transfer (records g–l). pCa values for records a–l are as follows: a and g = 4.0; b and h = 6.2; c and i = 6.0; d and j = 5.7; e and k = 9.0; f and l = 4.0. (b) Summary of the tension-pCa relationships for the control (filled circles) and R92Q (open circles) single cardiac myocytes shown in a. Tension values are normalized to the maximum tension value obtained in each myocyte at pCa 4.0.