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The aim of this study was to determine whether exercise training combined with beta-blocker treatment promotes additional cardiovascular benefits compared with either intervention on its own. For this we used 76 Wistar rats distributed among different groups: normotensive sedentary (NS), normotensive trained (NT), normotensive sedentary treated with betablocker (NS_BB), normotensive trained treated with beta-blocker (NT_BB), hypertensive sedentary (HS), hypertensive trained (HT), hypertensive sedentary treated with a beta-blocker (HS_BB), and hypertensive trained rats treated with beta-blocker (HT_BB). Exercise training consisted of 4 weeks of swimming for 60 min a day, 5 days a week. Hypertension was induced with L-NAME (4 weeks), whereas the control rats received saline, and both the control and test rats received nebivolol. The animals underwent surgery to directly record their blood pressure. The HS group showed higher mean arterial pressure (MAP) (P = 0.000), systolic arterial pressure (P = 0.000), and diastolic arterial pressure (P = 0.000) compared with NS. MAP was higher in the HS compared with the HT (P = 0.002), HS_BB (P = 0.018), and HT_BB (P = 0.015) groups. Hearts from the HS group had a higher percentage of collagen compared with the NS and HS_BB groups. The HT_BB and HT groups only had a higher percentage of cardiac collagen by comparison with the HS_BB group. The HT_BB group showed higher levels of macrophages and neutrophils by comparison with the HT and HS_BB groups. Thus, treatment with a beta-blocker combined with physical training was associated with increased cardiovascular benefits over either intervention alone. Key words: aerobic training, beta-blocker, nebivolol, hypertension. Le but de cette etude etait de determiner si l'exercice physique combine a un beta-bloquant confere des benefices cardiovasculaires supplementaires comparativement aux deux interventions prises de maniere isolee. Nous avons utilise 76 rats Wistar : normotendus sedentaires (NT), normotendus entraines (NE), normotendus sedentaires traites avec un beta-bloquant (NS_BB), normotendus entraines traites avec un beta-bloquant (NE_BB), hypertendus sedentaires (HS), hypertendus entraines (HE), hypertendus sedentaires traites avec un beta-bloquant (HS_BB) et hypertendus entraines traites avec un beta-bloquant (HE_BB). L'entrainement a consiste en une periode de natation de 60 minutes-[jour.sup.- 1], 5 jours-[semaine.sup.-1]. L'hypertension a ete induite par le L-NAME (4 semaines) et les rats controles ont recu de la saline, alors que les deux groupes ont recu du nebivolol. Les animaux ont subi une chirurgie afin d'enregistrer directement la pression sanguine. Le groupe HS presentait une pression arterielle moyenne (PAM) (P = 0,000), une pression arterielle systolique (P = 0,000) et une pression arterielle diastolique (P = 0,000) plus elevees, comparativement au groupe NS. La PAM etait plus elevee chez le groupe HS comparativement au groupe HE (P = 0,002), au groupe HS_BB (P = 0,018) et au groupe HE_BB (P = 0,015). Le groupe HS presentait le niveau de collagene cardiaque le plus eleve comparativement aux groupes NS et HS_BB, les groupes HE_BB et HE presentant un pourcentage de collagene plus eleve comparativement au groupe HS_BB seulement. Les zones comportant des macrophages et des neutrophiles etaient plus grandes chez le groupe HE_BB comparativement aux groupes HE et HS_BB. Le traitement au beta-bloquant associe a l'exercice physique confere des benefices cardiovasculaires. [Traduit par la Redaction] Mots-cles: entrainement aerobie, beta-bloquant, nebivolol, hypertension., Introduction Physical training has been used as an adjuvant in the treatment of hypertension. The goal is to reduce the values for blood pressure (BP) at rest, and thereby reduce [...]

Purpose: This study aimed to analyze the hemodynamic and cardiac effects of direct renin inhibitor (DRI) treatment and swimming training in hypertensive rats. Methods: Seventy-seven rats were divide into eight groups: sedentary normotensive (SN), trained normotensive (TN), sedentary normotensive treated with DRI (SN_DRI), trained normotensive treated with DRI (TN_DRI), sedentary hypertensive (SH), trained hypertensive (TH), sedentary hypertensive treated with DRI (SH_DRI), trained hypertensive treated with DRI (TH_DRI). Swimming training occurred for up to 60min, five times a week for four weeks. The hypertensive animals were treated with 20 mg · kg-1 · day-1 L-NAME for four weeks. Groups treated with DRI received 10mg · kg-1 · day-1 of aliskiren for four weeks. After the treatment period, all the animals underwent femoral artery catheterization surgery for direct measurement of cardiovascular variables. Results: The SH group presented hypertension (136.4±5.0mmHg) compared to the SN (107.1 ±1.7mmHg). The TH group showed lower mean arterial pressure (MAP) than the SH (121.1 ±1.3 mmHg), but the treatment with DRI did not attenuate hypertension (128.2 ± 4.9 mmHg). The analysis of collagen areas demonstrated that treatment with DRI may attenuate cardiac remodeling in situations of hypertension, in the condition of treatment alone or combined with physical training. Conclusion: Both interventions in combination may be more effective at reducing cardiovascular risk in hypertensive subjects. [ABSTRACT FROM AUTHOR]

We investigated the involvement of nitric oxide (NO) and reactive oxygen species (ROS) on autonomic cardiovascular parameters, vascular reactivity, and endothelial cells isolated from aorta of monosodium glutamate (MSG) obese rats. Obesity was induced by administration of 4 mg/g body wt of MSG or equimolar saline [control (CTR)] to newborn rats. At the 60th day, the treatment was started with N(G)-nitro-L-arginine methyl ester (L-NAME, 20 mg/kg) or 0.9% saline. At the 90th day, after artery catheterization, mean arterial pressure (MAP) and heart rate were recorded. Plasma was collected to assess lipid peroxidation. Endothelial cells isolated from aorta were evaluated by flow cytometry and fluorescence intensity (FI) emitted by NO-sensitive dye [4,5-diaminofluoresceindiacetate (DAF-2DA)] and by ROS-sensitive dye [dihydroethidium (DHE)]. Vascular reactivity was made by concentration-response curves of acetylcholine. MSG showed hypertension compared with CTR. Treatment with L-NAME increased MAP only in CTR. The MSG induced an increase in the low-frequency (LF) band and a decrease in the high-frequency band of pulse interval. L-NAME treatment increased the LF band of systolic arterial pressure only in CTR without changes in MSG. Lipid peroxidation levels were higher in MSG and were attenuated after L-NAME. In endothelial cells, basal FI to DAF was higher in CTR than in MSG. In both groups, acetylcholine increased FI for DAF from basal. The FI baseline to DHE was higher in MSG than in CTR. Acetylcholine increased FI to DHE in the CTR group, but decreased in MSG animals. We suggest that reduced NO production and increased production of ROS may contribute to hypertension in obese MSG animals., (Copyright © 2014 the American Physiological Society.)