ABC | Volume 113, Nº5, November 2019

Original Article Sousa et al. Antioxidant effect of rat environmental enrichment Arq Bras Cardiol. 2019; 113(5):905-912 Modifications to the standard caging to create enriched environments that allow improved motor activity, visual activity, exploration and social interactions have been associated with significant behavioural changes and improvements in overall health and well-being. 45 Overall health and well-being are related to lower levels of cortisol and blood pressure; however few studies show its effects on redox system in the hypertensive animals. 46 Conclusion The physiological effects of environmental enrichment are varied, but improved animal welfare and cognitive properties appear to be clear benefits. 15,47 Our study presents limitations since the laboratory environment places several physical and operational restrictions on the methods and the extent of the enrichment offered to the research mice. These limitations stimulate our ability to use different methods and produce maximum environmental enrichment. Despite the limitations collectively, our results suggested that environmental enrichment conferred antioxidant effects on the ventrolateral medulla and kidneys, probably contributing to MAP reduction and minimizing oxidative damage in renovascular hypertensive rats. We suppose that the enrichment may have made MAP of 2K1C-EE rats similar to SHAM rats by reducing levels of oxidative stress in the ventrolateral medulla, kidneys and heart probably because it reduced Ang II levels in those tissues. However, the effect of environmental enrichment on the renin-angiotensin system is still unknown. No studies were found that show the relationship between enriched environment and the renin-angiotensin system in hypertensive rats. Certainly, new studies should be conducted to clarify this issue. Acknowledgements Frank Silva Bezerra would like to express their gratitude to CAPES for your Post-Doctoral fellowship (CAPES-PVEX-Process # 88881.172437/2018-01) in the Interdepartmental Division of Critical Care Medicine, St. Michael’s Hospital, University of Toronto, Toronto, ON, Canada. Author contributions Conception and design of the research, Analysis and interpretation of the data, Statistical analysis and Writing of the manuscript: Sousa LE; Acquisition of data: Del Favero IF, Souza ABF; Critical revision of the manuscript for intellectual content: Bezerra FS, Souza ABF, Alzamora AC. Potential Conflict of Interest No potential conflict of interest relevant to this article was reported. Sources of Funding There were no external funding sources for this study. Study Association This study is not associatedwith any thesis or dissertationwork. 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