Figure 3. Effect of in situ contraction duration on skeletal muscle Ca²⁺–calmodulin-dependent protein kinase II expression and phosphorylation.

Skeletal muscle extract proteins were immunoblotted for CaMKII expression (top panel) and phospho-Thr²⁸⁷CaMKII (middle panel). The bottom panel is signal intensity for phospho-Thr²⁸⁷CaMKII relative to CaMKII expression. Representative immunoblots are shown and CaMKII isoforms are indicated; C, contralateral unstimulated muscle: STIM, electrically stimulated to contract, CON: contralateral muscle. Data are mean ± s.e.m., n = 8–12; *Different from time 0, P < 0.05; (*) borderline different compared with time 0, P = 0.069; +different from time 10 s, P < 0.05; #different from corresponding CON time.