Swimming does not alter nociception threshold in obese rats submitted to median nerve compression.

Abstract

OBJECTIVES: We, herein, analyzed the effect of swimming on nociception threshold and peripheral nerve regeneration in lean and obese rats submitted to median nerve compression. METHODS: To induce obesity, newborn male Wistar rats received injections of monosodium glutamate (MSG), whereas the control (CTL) group received saline. The animals were separated into 6 groups; control and obese (CTL and MSG), control and obese with lesion (CTL LES and MSG LES), and control and obese with lesion submitted to physical exercise (CTL LES PE and MSG LES PE). RESULTS: Median nerve compression reduced nociception threshold in CTL LES and MSG LES rats. Swimming effectively altered nociception only in CTL LES PE animals. Lean and obese animals displayed histological differences, when compared to sedentary animals, and exercise improved axon regeneration in both groups. The brain-derived neurotrophic factor and GAP 43 protein expression was greater in animals submitted to nervous compression without alteration by exercise. DISCUSSION: In conclusion, swimming, a conservative treatment for peripheral nerve lesions, was not able to improve the nociception threshold in obese rats.