Objective To measure the relationship between responses of blood pressure to exercise stress and changes of endothelium dependent vasodilatation in rest blood pressure well-controlled patients with hypertension.
Method 60 rest blood pressure were well-controlled patients with hypertension were divided into two groups: exercise hypertension (Group A) and normal exercise blood pressure (Group B), and 30 normal persons were cotrol group (Group C). Endothelium-dependent vasodilatation was assessed in the brachial artery by high resolution ultrasound technique before exercise and exercise stress test was assessed by 6-min walking test. Blood pressure (BP) and heart rate was measured before, at the time of the end of exercise and at 10, 20, 30 min after exercise. The serum concentrations of nitric oxide (NO), endothelin -1(ET-1) were measured before exercise and at the time of the end of exercise.
Result Compared with group B and Group C, FMD% in Group A significantly decreased (p<0.05). Immediately after exercise, SBP, DBP, HR in three groups significantly increased and dropped down to the original level at 10 min after exercise. Compared with group B and group C, the change of SBP, DBP in group A was the more obvious. Before exercise the concentrations of NO in group A was the lower than group A and B (p<0.05). Immediately after exercise there was significant increase of NO in three groups, and the change in group B and C was the higher (p<0.05). Compared with group B and group C, the concentrations of ET-1 in group A were significantly increased before exercise. Immediately after exercise there was no significant change of the concentrations of ET-1 in three groups. There was significant negative correlation between increasing-range of DBP and FMD (p<0.05); There was significant negative correlation between increasing-range of SBP and the change of NO (p<0.05), significant positive correlation between increasing-range of DBP and the change of NO (p<0.05); There was no correlation between increasing-range of SBP or DBP and the change of ET-1, and there was no correlation between increasing-range of HR and the FMD or the change of NO and ET.
Conclusion BP could increase after exercise in rest blood pressure well-controled patients with hypertension. Endothelium dependent vasodilatation, the serum concentrations of NO, but not the serum concentrations of ET-1 could be related to change of DBP and SBP.
- endothelium dependent vasodilatation
- rest blood pressure
- exercise stress