title: Antioxidant capacity in rat skeletal muscle tissues determined by electron spin resonance.
abstract: The amount of radical scavenging activity in muscle is unknown. The present study examines whether electron spin resonance (ESR) could measure and distinguish antioxidant capacity in muscle with different contractile and metabolic characteristics. Specimens of the soleus, plantaris, gastrocnemius (deep/surface portions), heart and diaphragm were obtained from female Wistar rats (n=7; 12 weeks old). Scavenging activity against superoxide anions in these specimens were determined by ESR using a spin-trapping chemical (5,5-dimethyl-1-pyrroline-N-oxide). The ESR signal intensity of reaction mixtures containing muscle tissues was significantly lower in the heart, soleus, diaphragm and deep portion of the gastrocnemius than in the plataris and surface portion of the gastrocnemius. Thus, the amount of scavenging activity converted into superoxide dismutase activity was the highest in the heart, and higher in the soleus, diaphragm and deep portion of the gastrocnemius than in other muscles (ANOVA, P<0.01). In addition, scavenging activity significantly correlated with citrate synthase activity (r=0.72, P<0.01, n=42) and myoglobin content (r=0.63, P<0.01, n=42). These findings suggested that ESR and spin-trapping can be detect differences in free radical scavenging activity among muscle tissues with different metabolic characteristics.
authors.affiliation: Faculty of Education, Kanazawa University, Kakuma-machi, Kanazawa-city, Ishikawa 920-1192, Japan. masuda@ed.kanazawa-u.ac.jp
authors.forename: Kazumi
authors.initials: K
authors.lastname: Masuda
authors.forename: Kai
authors.initials: K
authors.lastname: Tanabe
authors.forename: Shinya
authors.initials: S
authors.lastname: Kuno
authors.forename: Aki
authors.initials: A
authors.lastname: Hirayama
authors.forename: Sohji
authors.initials: S
authors.lastname: Nagase
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D005260:Female; D016166:Free Radical Scavengers / Q000378:metabolism; D005609:Free Radicals / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000975:Antioxidants; D016166:Free Radical Scavengers; D005609:Free Radicals