Figure 3. Effect of pH on force and ATPase activity in a mechanically skinned bundle of myofibrils.

The results at pH 7.1 (left) are shown in the absence (continuous lines) and presence (dashed lines) of 10 mM BDM. In the right panels, the corresponding results obtained at pH 6.2 are shown. Upper recordings, force development; lower recordings, NADH absorbance. * Calibration of the absorbance signal. Preparation diameters, 180/140 μm; preparation length, 2.50 mm.