The effects of high-intensity exercise on skeletal muscle neutrophil myeloperoxidase in untrained and trained rats.

The primary purpose of this study was to examine the effects of high-intensity acute exercise on neutrophil infiltration in different muscle fiber types of untrained rats and to compare postexercise neutrophil accumulation in muscles of untrained and trained animals. The effect of high-intensity acute exercise on blood neutrophil degranulation reaction in trained animals was also elucidated. Neutrophil enzyme myeloperoxidase (MPO) was determined as a measure of neutrophil migration into muscles and blood neutrophil degranulation.

Isolation and characterization of myeloperoxidase from leukocytes of rat peritoneal fluid.

Myeloperoxidase (MPO) was isolated from rat peritoneal leukocytes with a yield of 51% and A430/A280 = 0.75 - 0.80, and its physicochemical properties were studied.

[The effect of muscle activity on the blood neutrophil system in rats].

The effect of muscular activity (MA) on the amount of different classes of leukocytes in the blood, concentrations of myeloperoxidase and lysozyme in the blood plasma, and neutrophils and phagocytosis parameters of these cells, were studied in rats. The MA resulted in a decrease of marker proteins (myeloperoxidase and lysozyme) concentration in neutrophils and an increase of their concentrations in the blood plasma. The neutrophil phagocytic activity decreased.

[The detection of neutrophilic myeloperoxidase in the skeletal muscles of rats after muscle activity].

Rat muscle infiltration by neutrophils after muscle activity (MA) was investigated on myeloperoxidase (MPO) concentration. MPO distribution in muscle subcellular fractions was also studied. Increase of MPO concentration in skeletal muscles was discovered after MA.

[The effect of physical exertion on the activity of calpains and myeloperoxidase level in skeletal muscles of rats].

It has been established that the activity of calpains and the amount of neutrophil myeloperoxidase in skeletal muscles of rats increases after the 24-48 h-rest, that followed an intensive single physical exercise. Adaptation which appears as a result of systematic physical exercises causes less pronounced changes in the activity of proteolytic enzymes. Free ubiquitin content in skeletal muscles remains unchanged during training and in posttraining periods.