Effects of running exercise on tibiae in ovariectomized rats.
- VernacularTitle:実験的骨粗しょう症モデルラットに及ぼす走運動の効果
- Author:
ATSUSHI KIUCHI
;
SATOSHI SHIMEGI
;
HITOSHI AMAGAI
;
ATSUYA OHNO
;
SHIGERU KATSUTA
- Publication Type:Journal Article
- Keywords:
postmenopausal osteoporosis;
ovariectomy;
exercise;
bone histomorphometry;
rat
- From:Japanese Journal of Physical Fitness and Sports Medicine
1997;46(1):77-85
- CountryJapan
- Language:Japanese
-
Abstract:
The effects of running exercise on bone histomorphometric parameters were examined in sham-treated (Sham) and ovariectomized (OVX) rats. The rats were either kept sedentary (C) or trained (T) on a rodent treadmill at 25 m/min, 30 min/day, 5 days/week for 10 weeks. Fat-free dry bone weight, bone mineral content (BMC), and histomorphometric parameters were assessed after excision of the tibiae at sacrifice. The results are summarized as follows
1) There were no significant differences in fat-free dry bone weight and BMC between OVX-C and Sham-C rats. However, BMC/body weight in OVX-C rats was significantly lower than in Sham-C animals. OVX-C rats had significantly lower trabecular bone volume at the proximal tibial metaphysis than Sham-C animals. Values of bone formation parameters were significantly higher in OVX-C rats than in Sham-C animals.
2) BMC/body weight in OVX-T rats was significantly higher than in OVX-C animals. OVX-T rats had a significantly higher trabecular bone volume at the proximal tibial metaphysis than OVX-C animals. There were no significant differences in bone formation parameters between OVX-T and OVX-C rats.
3) No significant differences were found in any parameters between sham-C and Sham-T rats.
These results suggest that (1) running exercise has a suppressive effect on bone loss after OVX, and (2) training-induced reduction of bone loss by OVX does not seam to be associated with facilitation of bone formation but with suppression of bone resorption.
