Introduction: Skeletal muscle is changed after stroke, but conflicting data exist concerning muscle morphology and oxidative enzyme capacity.
Methods: In 36 chronic stroke patients bilateral rectus femoris muscle biopsies were analyzed, and fiber type proportions and cross-sectional areas were determined by ATPase histochemistry. Enzymatic concentrations of citrate synthase (CS) and 3-Hydroxyacyl-coenzymeA-dehydrogenase (HAD) were determined using freeze-dried muscle tissue. Findings were correlated with clinical outcomes.
Results: In the paretic muscles the mean fiber area was smaller (P = 0.0004), and a lower proportion of type 1 fibers (P = 0.0016) and a higher proportion of type 2X fibers (P = 0.0002) were observed. The paretic muscle had lower CS (P = 0.013) and HAD concentrations (P = 0.037). Mean fiber area correlated with muscle strength (r = 0.43; P = 0.041), and CS concentration correlated with aerobic capacity (r = 0.47; P = 0.01).
Conclusions: In stroke survivors there is a phenotypic shift toward more fatigable muscle fibers with reduced oxidative enzymatic capacity that relates to clinical outcomes.
Keywords: histological techniques [E01.370.225.750]; immunohistochemistry [E01.370.225.750.551.512]; motor activity [G11.427.590.530.698]; muscle fibers; paresis [C10.597.636]; skeletal [A10.690.552.500.500]; staining and labeling [E01.370.225.500.620.670]; stroke [C10.228.140.300.775].
© 2016 Wiley Periodicals, Inc.