[Bone histomorphometry study on lumbar vertebrae microstructure of ovariectomized goats].

OBJECTIVE

To demonstrate the histomorphometric changes of postmenopausal osteoporosis (PMO) goat model after bilateral ovariectomy (OVX).

METHODS

Fifteen female goats were randomly enrolled into four groups: 3 goats without any treatment (group C), 3 goats sham-operated only (group S), 4 goats 6 months after OVX (group OVX6M), 5 goats 18 months after OVX (group OVX18M). On the 21st and 9th day prior to sacrifice, tetracycline was given to them in order to label the bone for dynamic study. The first lumbar vertebrae from each goat were reserved for bone histomorphometric study.

RESULTS

As compared with group C and S, the trabecular bone volume (TBV)/total tissue volume, TBV/sponge bone volume, mean trabecular plate thickness (MTPT) and mean trabecular plate density in OVX6M and OVX18M groups were significantly lower (P < 0.01, but MTPT: P < 0.05), while the mean trabecular plate space, surface/volume ratio of the trabecular bone, single labelled surfaces [Sfaces(s)], double labelled surfaces [Sfaces(d)], Sfaces (d + 1/2s), mean osteoid seam width, mineralization lag time, speed of bone formation in the tissue levela and osteoid maturation period were significantly higher (P < 0.01).

CONCLUSION

In OVX goats, bone loss accelerated, resulting in destroyed bone microstructure, fasten frequency of activation and high bone turnover. Therefore, the bone resorption process exceeds over the bone formation, successfully establishing a high turnover osteoporotic metabolic model.