Effects of ovariectomy on the function of osteoblasts in female SD rats in vivo / 中华创伤骨科杂志

ABSTRACT

Objective To investigate the functional changes of osteoblasts in female SD rats in vivo at different phases following ovariectomy and to analyze their mechanism. Methods 40 female SD rats aged 6 months were randomly divided into 2 groups the sham operated group and the ovariectomized (OVX) group. During the 4-month experiment, 10 rats from each group were sacrificed to have the serum and the 4th lumbar vertebrae specimens at the end of the 2nd week and the 16th week respectively. Serum bone gla protein (BGP), serum bone specific alkaline phosphatase (BALP) were measured. The excretive function and morphologic changes of the osteoblasts were observed under TEM (Transmission Electronic Microscope). Results In the OVX group, the levels of BGP and BALP all increased at the end of the 2nd week, but showed no significant difference from those in the control group at the end of the 16th week. TEM indicated osteoblasts were activated at the end of the 2nd week, but tended to be inactivated in the ovariectomized group at the end of the 16th week. Conclusions When estrogen decreases in ovariectomized rats, osteoblasts experience a short activated period, but their capacity of bone formation decreases in the end. Abnormal function of osteoblasts may play an important role in pathogenesis of osteoporosis.