| Keywords |
Spontaneously Hypertension rats (SHR) ; Treadmill exercise training ; Bone mineral density (BMD) ; Serum Ca. |
| Abstract |
There have been many researches that studied the influence of exercise on secondary bone loss by hypertension. However, the researches still have a little question. For a better understanding between exercise and bone mineral density (BMD), the purpose of this study was to examine the effects of treadmill exercise on bone metabolic turnover in Spontaneously Hypertension Rats(SHR). Six-week-old male, fourteen SHR, and seven Wister-Kyoto (WKY) rats were investigated on bone status including BMD and biomechanical markers from serum. After a week of stabilization, the rats were randomly divided into three groups: WKY control group (n=7, WKY), SHR control group (n=7, SC) and SHR treadmill exercise group (n=7, SE). Treadmill exercise training was performed at 20m/min, 60min/day, 5days/week for 16 weeks. All that rats were fed an commercial standard lab chow and allowed free access to tap water. At the end of the experimental period, the rats were sacrificed with blood drawn and femur were removed for analysis of BMD by dual energy x-ray absorptionmetry (DEXA). In SC group, blood pressure showed significant higher (p<.001) than that of WKY group with a lower BMD(p<.05), BMC(p<.01), bone mass(p<.01), serum Ca(p<.01) and adjusted Ca(p<.01). In SE group, blood pressure was significantly decreased (p<.001), there was no change in BMD, BMC and bone mass as well as serum bone metabolic markers compared with SC group. Blood pressure was negatively correlated with all femur bone indexes and serum Ca concentration(p<.01), and there was a positive correlation between femur bone indexes and serum Ca concentration(p<.01). Results indicated that although SHR showed characteristics of osteoporosis, and treadmill exercise training improves blood pressure but does not prevent bone loss. |