| Objective To investigate the effect of parathyroid hormone combined with calcitonin on osteoporosis and its mechanism of action, and to provide theoretical basis for clinical treatment. Methods One hundred female SD rats were randomly divided into 5 groups: sham operation group, ovariectomized group, parathyroid hormone group, calcitonin group, and combination drug group, with 20 rats in each group. Osteoporosis animal model was constructed by ovariectomy in rats. Bone mineral density (BMD) and bone mineral content (BMC) were determined. Serum E2 and bone metabolism-related biochemical indicators and markers were detected. Bone morphological changes were observed. Results Compared with those in the sham-operated group, BMD and BMC of the lumbar spine and femur, the maximum femoral load, and serum E2, Ca, P, and OPG levels were significantly lower in the ovariectomized group (P<0.05).The above-mentioned indicators in the drug combination group were significantly higher than those in the ovariectomized group (P<0.05).The serum levels of ALP, OC, and RANK in the ovariectomized group were significantly higher than those in the sham-operated group (P<0.05), and the above indicators in the combination group were significantly lower than in the ovariectomized group (P<0.05). In the ovariectomized group, the trabecular bone was significantly reduced, the arrangement was sparse and disordered, large-scale fracture occurred, and a large amount of fibrous tissue and bone cells were rare. In the combination drug group, there was more and more trabecular bone, the morphological structure was more regular, the bone cells were arranged neatly, the bone continuity was good, and the bone density was thick and uniform. Conclusion Parathyroid hormone combined with calcitonin enhances estrogen levels, regulates bone metabolism, increases BMD and BMC, improves biomechanical properties, improves bone histopathology, and provides anti-osteoporosis and bone protective function. |