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Background: Some normotensive sedentary individuals have an exaggerated increase in blood pressure (BP) during physical activity, which is a behavior that is called blood pressure hyper-reactivity., Objective: To investigate the effect of an aerobic exercise program (AEP) on blood pressure in individuals with blood pressure hyper-reactivity (BPH)., Methods: Ten male volunteers with BPH, aged 45 ± 10 years, referred to as the experimental group (EG), took part in an AEP on a treadmill, 3 times a week for two months. They were compared to 14 men with BPH, aged 48 ± 8 years, referred to as the control group (CG), who remained sedentary. The subjects were evaluated before and after the AEP by stress test for comparison purposes. We evaluated the initial, peak and test-end heart rates (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP)., Results: There a significant decrease in the initial SBP (-5%; p=0.01), initial DBP (-4.6%; p=0.01), peak SBP (-12.4%; p=0.001), peak DBP (-14.7%; p=0.03), final SBP (-4.6%, p=0.03) in the EG. The CG continued with its hyper-reactive behavior, which evolved to more exaggerated levels when the results before and after the study were compared (p<0.04). In the HR, there was an increase only in the final HR, of 11.3 bpm, after training (p=0.02). The test-peak VO2 increased by 4.4 ml.kg(-1) x min(-1) in the EG (p=0.01) and remained similar in the CG., Conclusion: The AEP normalized the behavior of the blood pressure hyper-reactivity in sedentary men.

Background: Hypertension (H) is associated with a large number of co-morbidities, including obesity. The correlation between two variables has been investigated., Objective: To analyze the correlation between the loss of body mass and blood pressure reduction in hypertensive patients undergoing exercising programs (EP)., Methods: One hundred eleven hypertensive patients with overweight or obesity were randomly divided into an experimental group (EG). Out of these, 57 (58 +/- 8.9 years old) participated in a three-month EP conducted three times a week in aerobic exercise sessions from 50% to 70% of VO2 peak for 30 to 60 minutes and resistance exercises; and a control group (CG) with 54 (60 +/- 7.7 years old) who did not participate in the EP. In the EG, blood pressure (BP) was measured before each session and the measurement of anthropometric variables (AV) at the beginning of the program and after three months. In the CG the BP and the VA were evaluated in the doctor's office at the beginning and at the end of the study. Data were expressed as mean +/- standard deviation (SD). Pearson correlation and t test were used. A value of p < 0.05 was considered significant., Results: In the CG there was no significant difference in AV and BP at the beginning and at the end of the study. In the EG, there was no significant alteration in the AV, however, there was blood pressure reduction of 12% in systolic BP (-17.5 mmHg, p = 0.001) and 9% in Diastolic BP (-8.1 mmHg, p = 0. 01) at the end of the study. There was no correlation between the AV and decrease in BP (r = 0.1)., Conclusion: The blood pressure reduction was not correlated with reduction of anthropometric measures after the exercising period.

Background: The effect of exercise on blood pressure (BP) is already known; however, the dose-response curve of the hypotensive effect of exercise in hypertensive individuals is yet to be clarified., Objective: To evaluate the dose-response curve of the number of sessions that are necessary to cause a hypotensive effect in hypertensive individuals., Methods: 88 individuals, aged 58 +/- 11 years, divided in Experimental group (EG), with 48 that participated in a physical exercise program (PEP), which consisted of 40 minutes of aerobic exercises performed 3x/week, for 3 months, at 70% of the VO2max, and muscular exercises at 40% of the maximal voluntary contraction (MVC) and Control Group (CG) with 40 individuals that did not participate in the PEP. The systolic (SAP) and diastolic (DAP) arterial pressures were measured before each of the 36 sessions in the EG and assessed by ambulatory blood pressure monitoring (ABPM) in the CG. Differences in BP, the variation rate (D%) and the maximum hypotensive effect (MHE%) were observed between sessions. The data were expressed as means +/- SD; the t test and correlation were used, with p<0.05 being considered significant., Results: There was no difference regarding BP values in the CG. The EG showed an important decrease of 15 mmHg in SAP and 7 mmHg in DAP, with a large part of this effect occurring as early as the first session and the majority up to the 5th session. There was a strong inverse correlation (R:-0.66) with the number of sessions., Conclusion: An important hypotensive effect was observed from the 1st session on and it was observed that the dose-response curve can be abrupt and decrescent, instead of flat.

Background: Rodents without a functional endothelin B (ETB) receptor develop salt-sensitive hypertension. The underlying mechanisms, however, are so far unknown. The ETB receptor is involved in endothelial function by modulating the activity of the endothelial nitric oxide synthesis as well as contributing to the control of endothelial prostacyclin synthesis. In the present study, we analysed whether salt alters endothelial function in rescued ETB receptor-deficient mice. We used mice with a rescue of the lethal phenotype of an ETB knockout. These mice were generated by crossbreeding ETB mice with dopamine-hydroxylase ETB transgenic mice., Methods: Adult rescued ETB-deficient mice were kept in parallel with wild-type control animals for 15 days on standard (0.2% NaCl) or salt-enriched (4% NaCl) chow, respectively. Systolic blood pressure was measured by the tail cuff method and endothelium-dependent and endothelium-independent vascular function was assessed in isolated aortic rings under isometric conditions., Results: Systolic blood pressure increased on salt-enriched chow in ETB receptor-deficient mice (166 +/- 12 mmHg), but neither in wild-type mice on high-salt diet (128 +/- 11 mmHg; P < 0.05) nor in ETB receptor-deficient mice on standard chow. The heart rate was similar in all groups at any point of time. Endothelium-dependent relaxation was impaired in ETB receptor-deficient mice (74 +/- 3 versus 96 +/- 5% of preconstriction for wild-type mice; P < 0.05) and was not significantly affected by a salt-enriched diet. Endothelium-independent relaxation was similar among all groups. Contractions to endothelin-1 were not significantly influenced by preincubation with the ETB receptor antagonist BQ-788, but were completely blunted by preincubation with the ETA receptor antagonist BQ-123 in all animals., Conclusion: Rescued ETB receptor-deficient mice develop salt-sensitive hypertension. Nevertheless, in this animal model of ETB receptor deficiency, endothelial function is impaired independent of salt-enriched diet or hypertension. This indicates that, in this model, salt-induced hypertension is not mediated by endothelial dysfunction.