Papel do exercício físico nas alterações comportamentais, na regulação hidroeletrolítica e no balanço simpato-vagal cardíaco no modelo de uso abusivo de esteróides anabolizantes em ratos

Abstract

The abuse of anabolic androgenic steroids (AAS), and off the sports scene, it is currently in big public health problem. Although studies on behavioral changes induced by AAS and electrolyte are well known, the same is not observed when these parameters are analyzed together (in the same study). In addition, late changes (in adulthood) induced by the use of AAS abuse in adolescence are even more rare. Thus, the main objective of this study was to assess possible behavioral changes, electrolyte and rat autonomic sedentary or physically active adults undergoing treatment with AAS in the juvenile phase. This study was submitted to the Ethics Committee of University Rural of Rio de Janeiro (CEPBE/IB/UFRRJ-014/2008), and followed the guidelines proposed by the "Guide for the Care and Use of Laboratory Animals" (National Institute of North American Health). A total of 40 young Wistar rats (40 days) and 10 pairs of residents (90 days). The animals were randomly divided into the following groups: proprionate treated with testosterone (PT) at a dose of 5mg/kg/day (im) or vehicle (corn oil) in the same volume and route of administration (control group, CTR) for 5 weeks uninterrupted. Both groups were subdivided into sedentary (or PTsed CTRsed) and physically active (or PTexe CTRexe). In the fourth week of administration (9 weeks of age), animals were tested for aggressiveness and the results showed a significant increase of this parameter (P <0.05) in PTsed in relation to its control (CTRsed). Interestingly, the increased aggressiveness was largely inhibited by resistive exercise, since there were no significant differences in parameters that assess aggression (actual attacks and threats) between the groups and PTexe CTRexe (P <0.05) and both are similar to CTRsed the control group. In the open field test showed a significant increase both the horizontal scanning (number of squares crossed / 5 min.) And vertical (number of rearings / 5 min.) And decrease in the immobility time compared to CTRsed PTsed group (P <0 , 05). Again, the EFR was able to reverse the effect produced by the AAS, as there was no difference in these parameters between groups and PTexe CTRexe (P <0.05) and both are similar to the control group CTRsed. In testing the elevated plus maze, no significant change in parameter the arms in any group and which probably indicates absence of anxiolytic in management protocols and EFR AAS used in this study. Electrolyte in the study increased significantly (p <0.05) in cumulative intake of water and sodium CTRexe from 60 minutes and so on until the end of the test, compared to other groups at baseline. The group treated with AAS and practiced physical exercise (PTexe) did not show this effect, suggesting that the PT was able to prevent the adaptive responses to the EFR. In the study of heart rate variability was observed that AAS treatment increased sympathetic modulation (decreased parasympathetic) in the sedentary group treated with PT and that this effect was totally blocked by EFR because there was no difference in cardiac vagal-sympathetic balance between groups and PTexe CTRexe (P <0.05) and both are similar to the control group CTRsed. The AAS treatment in the juvenile phase (adolescence) increased aggressiveness and exploratory activity of rats in adulthood and the exercise protocol used was effective in preventing such changes. Furthermore, the adaptive responses electrolyte of increased fluid intake induced by exercise have been blocked by the use of EAA in adolescence. It is possible that this effect maladaptive observed in animals treated with AAS physically active, may be explained at least in part, by increasing sympathetic modulation, known to salt and water retaining observed in the spectral analysis. Financial Support: National Council for Scientific and Technological Development and the Foundation for Research of the State of Rio de Janeiro.