ABC | Volume 110, Nº3, March 2018

Original Article Lemos et al Exercise improves splenic arterioles In SHR Arq Bras Cardiol. 2018; 110(3):263-269 It is well established that regular physical activity reduces AP in hypertensive individuals, without significant pressure changes in normotensive individuals. 38-40 In fact, several studies have suggested that exercise training intensity influences the pressure-lowering effect, with larger reductions being observed with lower exercise intensities. 40 We did not analyze the effect of training intensity, but our results clearly showed that the exercise protocol used caused an important AP decrease only in the SHR group. Pressure reduction was accompanied by both resting bradycardia and specific training-induced adjustment in splenic hypertensive arterioles. Resting bradycardia is considered to be an excellent hallmark for exercise training adaptation in humans and rats. 39-40 Thus, the bradycardia found in trained rats clearly demonstrates the effectiveness of the exercise protocol here used. Conclusion Considering our findings, we can conclude that exercise training was effective in reducing AP and improving splenic arteriolar morphometry in hypertensive rats. Briefly, these data strongly suggest that this improvement was associated with decreased sympathetic nerve activity. In addition, regression of hypertrophied splenic arteriole is the anatomic response to exercise training specific to the SHR group. These compensatory adjustments, by reducing local resistance and augmenting physical capacity, contribute to the training-induced, pressure‑lowering effect observed in hypertensive individuals. Author contributions Conception and design of the research: Barbosa Neto O; Acquisition of data: Lemos MP, Sordi CC; Analysis and interpretation of the data: Lemos MP, Mota GR, Marocolo Júnior M, Sordi CC, Chriguer RS, Barbosa Neto O; Statistical analysis: Lemos MP, Barbosa Neto O; Writing of the manuscript: Lemos MP; Critical revision of the manuscript for intellectual content: Mota GR, Marocolo Júnior M, Sordi CC, Chriguer RS, Barbosa Neto O. Potential Conflict of Interest No potential conflict of interest relevant to this article was reported. Sources of Funding This study was partially funded by Capes, CNPq and Fapemig. Study Association This study is not associatedwith any thesis or dissertationwork. Ethics approval and consent to participate This study was approved by the Ethics Committee on Animal Experiments of the Universidade Federal do Triângulo Mineiro under the protocol number #271/2013. 1. Silvestre JS, Levy BI. [Hypertension: microvascular complications]. 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