Amelioration of Age-related Blood Pressure and Sympathetic Activity Raised and Sleep Disturbance during Long-term Treadmill Exercise Training in SHR

• Main Authors: Tsung-Han Liu, 劉璁翰
• Other Authors: Cheryl C.H. Yang
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/75d3d2

碩士 === 國立陽明大學 === 腦科學研究所 === 100 === Abstract Background: The hypertensive patients and spontaneously hypertensive rats (SHRs) have been suggested to have higher blood pressure, sympathetic activity and worse sleep quality compared with normotensive controls. The antihypertensive effect of long-term exercise has been suggested to involve the modulation of the autonomic nervous system (ANS) and sleep architecture. However, it is still unknown about the correlations, time courses, and how ANS function and sleep architecture change during long-term exercise in hypertensive and normotensive ones. Hypothesis: The effect that amelioration of age-related blood pressure and sympathetic activity raised and sleep disturbance are correlated to exercise induced changes of ANS and sleep architecture in SHRs by long-term mild-intensity treadmill exercise, and the normotensive controls have different responses to the same exercise training protocol. Materials and Methods: Electroencephalogram, electromyogram, electrocardiogram and blood pressure were recorded for 24 hours each week in eight-week-old male SHRs and Wistar-Kyoto rats as normotensive controls. The training group rats exercised on the treadmill sixty minutes per day, five days per week for eight consecutive weeks, and the sedentary control group rats were handled to adapt to the treadmill without running. We used spectral analysis of heart rate variability as ANS activity and analyzed EEG and EMG parameters for sleep architecture. Results: The first section: Compared with baseline (W0) and age-matched sedentary WKYs, 24-hour mean blood pressure (MBP), R-R interval (RR), heart rate total power (TP), HF (high frequency), total paradoxical sleep (PS) time had increased, and total awake (AW) time, AW duration per stage, total quiet sleep (QS) time, and EEG delta, theta, beta wave powers had decreased with age in sedentary SHRs . However, only increased of RR, total AW time, and decreased of EEG wave powers can be obviously observed with age in sedentary WKYs. The second section: Compared with sedentary SHRs, total QS time was higher, and all parameters except RR, TP and HF had ameliorated the changes with age, and even had no significant differences with W0 in running SHRs. In the time course of exercise impacts, antihypertensive effect happened in SHRs after one week exercise, decreased of vascular sympathetic activity after five week exercise, decreased of total PS time after six week exercise, and increased of total QS time after five week exercise. The third section: Compared with sedentary groups in each running SHRs and WKYs, exercise had decreased of BP, blood pressure low frequency (BLF), total PS time but increased of low frequency percentage (LF%), total QS time, and ameliorated of decreasing in EEG wave powers in running SHRs. However, exercise had increased of TP, HF and total AW time in running WKYs. Conclusions: Long-term exercise prevents the elevation of BP and maintains BP at the developmental stage, and also ameliorates age-related deterioration of vascular sympathetic activity and sleep quality in SHRs. However, long-term exercise increases of heart rate TP and parasympathetic activity in WKYs.