c-met protein levels and phosphorylation after muscle injury in WT, uPA^−/−, and PAI-1^−/− mice. Muscles from WT, uPA^−/−, and PAI-1^−/− mice collected from uninjured control mice (Con) and on days 1, 3, 5, and 10 after cardiotoxin injury. (Top) Muscle homogenates subjected to c-met immunoprecipitation and then Western blotting for c-met and phosphotyrosine (pTyr). (Bottom) Densitometric measurements performed for c-met and pTyr and normalized to c-met level in control sample for each series of samples obtained for each strain. Bars represent ± SE; n = 6 per time point. *Mean value significantly smaller than that for WT mice (P < .05). **Mean value significantly larger than that for WT mice (P < .05).