Differential Effect of Calsequestrin Ablation on Structure and Function of Fast and Slow Skeletal Muscle Fibers

Figure 5

Ablation of CASQ isoforms resulted in prolongation of the twitch parameters in both EDL and Soleus. (a) and (b) Time to peak (i.e., from the stimulus to the tension peak) was prolonged in EDL from CASQ1-null, and even more in dCASQ-null, compared to WT. This effect is not seen in Soleus. (c) and (d) On the other hand, time to base (i.e., from stimulus back to base line at the end of relaxation) was prolonged compared to WT in both EDL and Soleus muscles, more in dCASQ-null than in CASQ1-null mice (EDL: WT 𝑛=8, CASQ1-null 𝑛=10, dCASQ null 𝑛=9, Soleus: WT 𝑛=8, CASQ1-null 𝑛=10, dCASQ null 𝑛=10). *Significantly different from WT; #significantly different from CASQ1-null.

(a)

(b)

(c)

(d)