Fig. 6. The predicted effect of the thick and thin filament lattice and restriction within the cylindrical sarcolemma on the time dependence of D for arginine phosphate. (A) The effect of the nm-scale thick and thin filament lattice, using a porosity of 0.86, on the relative D of arginine phosphate. Note the short time required for D to reach a steady-state value. (B) The effect of restriction within the sarcolemmal membrane of a cell with a radius of 150 µm on the relative D of arginine phosphate (note: axes are different than A). (C) The predicted time dependence of the absolute D of arginine phosphate in an unrestricted environment (solid line), in the presence of the thick and thin filament lattice (dotted line), and when restricted within the sarcolemmal membrane of a cell with a radius of 150 µm (dashed line). The lower squares depict the raw data collected for D of arginine phosphate (Fig. 4A), and the upper squares show the predicted D of arginine phosphate if the effects of the thick and thin filament lattice and restriction within the sarcolemma are removed. The upper squares therefore predict the pattern of D time dependence imposed by residual, µm-scale barriers. See text for additional details.