Histochemical Changes of Skeletal Muscle in Equine Acute Rhabdomyolysis

Abstract. In two mixed breed horses that died due to acute rhabdomyolysis, were realized histopathology and histochemical exams. There were examined the following muscles: mean gluteus, semitendinosus and semimembranosus. Histopathology exam revealed some specific lesions for acute rhabdomyolysis, such as interfibrillar edema, granular and vacuolar degeneration and Zenker myofiber necrosis. Histochemical exam noticed in affected myofibers normal glycogen and amylase-resistant polysaccharide complex. Myofibers lesions degree was more severe in muscle cells that were enriched in PAS positive amylase-resistant polysaccharide material. A certain cause of acute rhabdomyolysis in both horses was polysaccharide storage myopathy in which the muscular presence of amylase-resistant polysaccharide complex is the pathognomonic finding