Figure 1. [Ca²⁺]_i transients are much slower in developing than in mature skeletal muscle cells.

The response to a single electrical stimulation pulse in cultured rabbit myotubes (A) and adult EDL (continuous line) and soleus (dotted line) muscle fibres (B). Note the markedly different time scales in A and B. A is adapted from Kubis et al. (2003), with permission of the American Physiological Society; B is from Baylor & Hollingworth (2003).