title: Implementation of periodic acid-thiosemicarbazide-silver proteinate staining for ultrastructural assessment of muscle glycogen utilization during exercise.
abstract: Distribution of glycogen particles in semithin and ultrathin sections of biopsy samples from human muscles subjected to either short- or long-term running were investigated using PAS and Periodic Acid-ThioSemiCarbazide-Silver Proteinate (PA-TSC-SP) staining methods. Glycogen particles were predominantly found immediately under the sarcolemma or aligned along the myofibrillar I-band. After long-term exhaustive exercise type-1 fibers with a few or no glycogen particles in the core of the fibers were frequently observed. The subsarcolemmal glycogen stores of these "depleted" type-1 fibers were about three times as large as after exhaustive short-time exercise. Another indication of utilization of subsarcolemmal glycogen stores during anaerobic exercise was that many particles displayed a pale, rudimentary shape. This observation suggests fragmental metabolization of glycogen. Thus, depending on type of exercise and type of fiber differential and sequential glycogen utilization patterns can be observed.
mesh_terms: D000293:Adolescent; D000328:Adult; D006003:Glycogen / Q000378:metabolism*; D006651:Histocytochemistry; D006801:Humans; D008297:Male; D008854:Microscopy, Electron; D009132:Muscles / Q000378:metabolism / Q000648:ultrastructure*; D010504:Periodic Acid; D010503:Periodic Acid-Schiff Reaction; D005082:Physical Exertion; D012420:Running; D012663:Semicarbazides; D012836:Silver Proteins
chemical_list: D012663:Semicarbazides; D012836:Silver Proteins; D010504:Periodic Acid; C005151:thiosemicarbazide; D006003:Glycogen; C009288:metaperiodate