Muscle force measurements in Mariusz mice.

<p>(<b>A</b>) Morphometric measurement of cross-sectional area of Mariusz muscles in histological sections normalized to the area of the muscle in wild type controls (n = 3 mice each genotype at 5 weeks of age; n = 50 fibres counted per sample). Muscle abbreviations are: FDS, Flexor Digitorum Sublimis; FCR, Flexor Carpi Radialis; ECU, Extensor Carpi Ulnaris; ECR, Extensor Carpi Radialis. ‘Area forelimb’ refers to the entire area of the forelimb to emphasize the size difference between Mariusz mice and littermates controls. (<b>B</b>) Example trace of a tetanic contraction in a Mariusz soleus muscle and a wild type control. (<b>C</b>) Mean peak tetanic force for control (n = 5) and Mariusz (n = 6) mice with SEM shown by error bars. (<b>D</b>) Mean isometric stress of the soleus muscle for wild type (n = 5) and Mariusz (n = 6) mice with SEM shown by error bars. (<b>E</b>) The mean ratio of the mass of the soleus muscle to the mass of the mouse for control (n = 5) and Mariusz (n = 6) mice with SEM shown by error bars. (<b>F</b>) The mean maximum contraction velocity of the soleus muscle in wild type control (n = 4) and Mariusz (n = 5) mice with SEM shown by error bars. P-values: * <i>P</i><0.05; ** <i>P</i><0.01.