Exercise Training Restores Iimpairment on Cardiovascular Autonomic Modulation in Aged Ovx Rats

The aim was to evaluate the impact of exercise training on hemodynamic parameters and autonomic control in old ovariectomized rats. Female old OVX rats (~18 wks. of age) were divided into 3 groups (n=8): old control (OC), old sedentary ovariectomized (OVX) and old trained ovariectomized (OVXt). The ovariectomy was performed by bilateral ovaries removal. The exercise training was performed on a treadmill for 8 weeks. Arterial pressure (AP) and heart rate (HR) signals were directly recorded in conscious rats. Assessment of autonomic modulation was performed by spectral analysis. The OVX group (130±5.05mmHg) showed increased AP compared to OC group (116 ± 2.56mmHg). Exercise training induced resting bradycardia (344± 7 bpm) compared to OC (375±14bpm) and OVX groups (384±10bbpm). The ovariectomy induced reduction in standard deviation (SD) of pulse interval (OVX:3.80 ± 1.08 vs. OC:8.82±1.96ms2) and RMSSD (OVX:3.15± 1.17 vs. OC:11.41±2.76ms). In addition, there was an increase in the SD of systolic AP in the OVX group (7.41±1.69mmHg2) compared to OC group (4.14±1.29mmHg2). Exercise training attenuated the changes in cardiac and vascular autonomic modulation (SD‐PI: 11.25±8.9ms2, RMSSD:11.48±8 ms and SD‐SAP:4.82±3.12 mmHg2). These data suggests that exercise training reduced AP and HR associated with attenuation of cardiovascular autonomic modulation in aged rats submitted to ovarian hormones deprivation.