Treadmill exercise suppressed age-related increases in blood pressure and vascular sympathetic activity in spontaneously hypertensive rats, disrupting their positive correlation.
Does treadmill exercise prevent hypertension and alter the correlation between vascular sympathetic activity and blood pressure in spontaneously hypertensive rats?
In a rat model of hypertension, exercise training prevented age-related increases in blood pressure and disrupted its correlation with vascular sympathetic activity.
BACKGROUND: Hypertension usually accompanies the elevated sympathetic activity and sleep interruption. Few researches explored the dynamic changes and possible correlations in cardiovascular functions and sleep patterns during the development of hypertension. In contrast, exercise training provides several benefits on cardiovascular and sleep function in hypertensive subjects. However, controlling various factors during a long period of exercise training is difficult in hypertensive subjects, an animal model may be essential. This study aimed to explore dynamic changes in cardiovascular functions and sleep patterns during the development period of hypertension (10-20 weeks old) in spontaneously hypertensive rats (SHRs) and effects of exercise intervention. METHODS: We used the treadmill exercise model for 8 weeks and started when SHRs were 12 weeks old. Electroencephalogram, electromyogram, electrocardiogram, and blood pressure (BP) were recorded simultaneously for 24 hours once a week over 11 weeks. RESULTS: Untrained SHRs revealed the age-related increments in BP, and the significant increasing slopes of differences on BP and vascular sympathetic activity were observed during the development period of hypertension. Compared with untrained rats, age-related increases in BP and vascular sympathetic activity were significantly suppressed in trained SHRs. Nevertheless, trained SHRs showed more quiet sleep time at partial weeks. The positive correlation between the differences from 10 weeks of vascular sympathetic activity and BP was disappeared in trained SHRs. CONCLUSIONS: There existed the significant correlation between the dynamic changes of vascular sympathetic activity and age-related elevation of BP during the development period of hypertension; however, exercise prevented hypertension and disrupted this correlation.
Li et al. (Wed,) conducted a other in Hypertension. Treadmill exercise vs. Untrained rats was evaluated on Dynamic changes in blood pressure and vascular sympathetic activity. Treadmill exercise suppressed age-related increases in blood pressure and vascular sympathetic activity in spontaneously hypertensive rats, disrupting their positive correlation.