Additional in vitro contractile properties of directly stimulated EDL muscles.

***Muscle twitches recorded in mutant mice are smaller and have a longer time-to-peak tension. Reduced absolute values are due to smaller muscles in mutants because normalized twitch forces are not different from wild-type. Similar outcome is shown for tetanic force in Figure 3. MW:BW ratio%, percent muscle to body-weight; Pt(g), absolute twitch force; Pt (N/g), twitch force normalized to muscle weight; TPT, time-to-peak twitch tension; 1/2RT-twitch half-relaxation time; N, Newtons (force); ms, milliseconds.