Comparison of the effects of parathyroid hormone (1-34), alendronate sodium and simvastatin on osteoporotic rats

Mu Shu-lin; Zhang Liu; Tian Fa-ming; Mu Shu-min; Sun Li-xia; Chu Li-ming

doi:10.3969/j.issn.2095-4344.2016.46.002

Abstract：BACKGROUND:Bone resorption drugs in the treatment of osteoporotic fracture are stil controversial. The development of new drugs, especial y drugs in the promotion of bone formation, become more important and urgent. OBJECTIVE:To compare the effects of parathyroid hormone (1-34), alendronate sodium and simvastatin on bone loss in ovariectomized rats. METHODS:Thirty female Sprague-Dawley rats aged 3 months were randomized into five groups of six animals in each group. Al rats but those in sham group received dual ovariectomy (OVX) and treated by vehicle (OVX+V), parathyroid hormone (1-34) (5 days per week at a dose of 20μg/kg, OVX+P), alendronate sodium (70μg/kg/wk, OVX+A), simvastatin (5 mg/kg/d, OVX+S). Three months later, al rats were sacrificed. Dual energy X-ray method was used to measure bone density of L4 vertebra. Bone histomorphometry was utilized to analyze cancel ous bone mass and bone microstructure. Compression test was performed on the L5 vertebra for the maximum loading and elastic modulus. RESULTS AND CONCLUSION:(1) Bone density:The bone density from high to low levels was OVX+P group, sham group, OVX+A group, OVX+S group, and OVX+V group. No significant difference in bone density was detectable between the OVX+P and sham groups, but significant differences in bone density were determined between any other two groups (P<0.05). (2) Bone histomorphometry:Relative volume of trabecular bone was significantly lower in the OVX+V group than in other groups. Relative volume of trabecular bone was remarkably higher in the OVX+P group than in the OVX+A group and OVX+S group. (3) Biomechanical properties:Biomechanical properties were noticeably lower in the OVX+V group than in other groups. Biomechanical properties were remarkably higher in the sham group and OVX+P group than in the OVX+S group and OVX+A group. (4) These findings indicated that under the dosage and intervention period used in the present study, parathyroid hormone (1-34), alendronate sodium and simvastatin showed anti-osteoporosis effect on OVX rats in a descending manner.