Influência benéfica de diferentes tempos de exercício físico sobre a drogadição induzida por morfina em ratos: aspectos comportamentais e moleculares

Abstract

Morphine is an opioid of high clinical employment, whose analgesic properties are accompanied by euphoria and well being, thus favoring drug addiction, which constitutes a serious public health problem. Drug addiction by opioids has driven the search for new treatments, but so far, those used clinically are only palliative. Physical exercise has shown beneficial in addition. But the lack of data in the literature stimulated the development of this study, whose objective was to evaluate possible molecular and behavioral adaptations resulting from different times of physical exercise in animals exposed to morphine. Wistar rats were subdivided into sedentary, short, medium and long term exercise and submitted to swimming protocol for 0, 14, 28 and 42 days, respectively. In the last week of exercise, the animals were submitted to a paradigm of morphine-conditioned place preference (CPP) (4 mg/Kg), followed by molecular analyzes involving the dopaminergic system and glucocorticoid receptor in the nucleus accumbens and hippocampus (CEUA 9373231116- UFSM). Our results show that addition of minor preference for drug in exercised groups showed less of the transporter dopamine (DAT) immunoreactivity , dopaminergic receptors type 1 and 2 (D1R and D2R) and glucocorticoid (GR) compared to sedentary group. Our study demonstrates that physical exercise, regardless of uptime, was able to modify behavioral parameters of addition per morphine, possibly through molecular adaptations in targets related to the reward system. From this study it is possible to propose physical exercise as a therapeutic approach to be strategically included in the treatment of opioid drug addiction.