Swim training does not protect mice from skeletal muscle oxidative damage following a maximum exercise test.

We investigated whether swim training protects skeletal muscle from oxidative damage in response to a maximum progressive exercise. First, we investigated the effect of swim training on the activities of the antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), in the gastrocnemius muscle of C57Bl/6 mice, 48 h after the last training session. Mice swam for 90 min, twice a day, for 5 weeks at 31°C (± 1°C).

Divergent cytokine response following maximum progressive swimming in hot water.

Exercise promotes transitory alterations in cytokine secretion, and these changes are affected by exercise duration and intensity. Considering that exercise responses also are affected by environmental factors, the goal of the present study was to investigate the effect of water temperature on the cytokine response to maximum swimming. Swiss mice performed a maximum progressive swimming exercise at 31 or 38°C, and plasma cytokine levels were evaluated immediately or 1, 6 or 24 h after exercise.

Electrophysiological characterization and molecular identification of the Phoneutria nigriventer peptide toxin PnTx2-6.

A cDNA with 403 nucleotides encoding the precursor of the toxin PnTx2-6 was cloned and sequenced. Subsequent analysis revealed that the precursor begins with a signal peptide and a glutamate-rich propeptide. The succeeding peptide confirmed the reported sequence of PnTx2-6.