Herrera Naiara A, Jesus Isley, Shinohara André L, Dionísio Thiago J, Santos Carlos F, Amaral Sandra L
aJoint Graduate Program in Physiological Sciences, PIPGCF UFSCar/UNESP, São Carlos bDepartment of Biological Sciences, Bauru School of Dentistry, University of São Paulo cDepartment of Physical Education, São Paulo State University (UNESP), Science Faculty, Bauru, São Paulo, Brazil.
J Hypertens. 2016 Oct;34(10):1967-76. doi: 10.1097/HJH.0000000000001032.
Although aerobic exercise training has been recommended as nonpharmacological treatment of high blood pressure, the mechanisms of training-induced blood pressure lowering effects in dexamethasone (DEX)-induced hypertension remain unclear. Therefore, the aim of this study was to investigate the preventive role of exercise training in counteracting DEX-induced hypertension.
Rats were submitted to aerobic exercise training for 8 weeks or kept sedentary and then treated with DEX (50 μg/kg/day, s.c.) or saline injections for 14 days. Thereafter, all rats underwent carotid artery catheterization, and cardiovascular autonomic modulation was evaluated by spectral analysis. In addition, soleus muscle was collected for morphometric and protein level analysis.
DEX treatment increased arterial pressure concomitantly with an increase in low-frequency spectral power of systolic arterial pressure and low frequency in pulse interval (94.11 and 58.58%, respectively), and a decrease in high-frequency spectral power of pulse interval (-12.05%). Capillary density (-25.87%), capillary-to-fibers ratio (-21.22%), vascular endothelial growth factor level (-15.10%), B-cell lymphoma 2 (Bcl-2) level (-16.40%) and Bcl-2/Bcl-2 associated X protein ratio (-27.14%) were all decreased after DEX treatment. Exercise training attenuated DEX-induced increase in arterial pressure accompanied by an attenuation of low-frequency spectral power of systolic arterial pressure, low frequency in pulse interval increases and high-frequency spectral power of pulse interval decrease. Training also prevented the decrease in capillary density (+44.43%), capillary-to-fibers ratio (+36.97%), vascular endothelial growth factor (+16.46%), Bcl-2 (+15.21%) protein level and Bcl-2/Bcl-2-associated X protein ratio (+30.93%).
These results demonstrate that exercise training improves cardiovascular autonomic balance to the heart associated with an improvement in sympathetic modulation of vascular tone and microcirculatory function in the skeletal muscle of DEX-induced hypertensive rats.
尽管有氧运动训练已被推荐作为高血压的非药物治疗方法，但地塞米松（DEX）诱导的高血压中训练诱导的血压降低作用机制仍不清楚。因此，本研究的目的是探讨运动训练在对抗DEX诱导的高血压中的预防作用。
将大鼠进行8周的有氧运动训练或保持久坐不动，然后用DEX（50μg/kg/天，皮下注射）或生理盐水注射14天。此后，所有大鼠均进行颈动脉插管，并通过频谱分析评估心血管自主神经调节。此外，收集比目鱼肌进行形态计量和蛋白质水平分析。
DEX治疗使动脉压升高，同时收缩期动脉压的低频谱功率和脉搏间期的低频增加（分别为94.11%和58.58%），脉搏间期的高频谱功率降低（-12.05%）。DEX治疗后，毛细血管密度（-25.87%）、毛细血管与纤维比例（-21.22%）、血管内皮生长因子水平（-15.10%）、B细胞淋巴瘤2（Bcl-2）水平（-16.40%）和Bcl-2/Bcl-2相关X蛋白比例（-27.14%）均降低。运动训练减轻了DEX诱导的动脉压升高，同时收缩期动脉压的低频谱功率、脉搏间期低频增加和脉搏间期高频谱功率降低也有所减轻。训练还预防了毛细血管密度（+44.43%）、毛细血管与纤维比例（+36.97%）、血管内皮生长因子（+16.46%）、Bcl-2（+15.21%）蛋白水平和Bcl-2/Bcl-2相关X蛋白比例（+
