Figure 1.

Force (A) and Ca²⁺ sensitivity (B) in skinned PMs and slow-twitch skeletal SOL muscles from 6- to 9-mo-old R58Q and WT mice. For measurements in PMs and SOL muscles, 2F and 2M R58Q and 1F and 3M WT mice were used. For measurements in EDL muscles (negative control), 1F for R58Q (10 fibers) and 1F WT (10 fibers) were used. The exact number of animals and fibers used in contractile measurements is listed in Table 1. Data are average of n ± sem animals (fibers for EDL). *P < 0.05 (Student’s t test).