【Animal Experiment】-Effects of different intervention programs of simvastatin on bone quality of osteoporotic rats

  Objective: To study and compare the effects of simvastatin on bone loss and bone loss in ovariectomized rats.

  Methods: 32 3-month-old SD rats were randomly divided into 4 groups, 8 in each group: sham operation (A) group, ovariectomy (B) group, ovariectomy + simvastatin intervention group in the first half of the year (C) and the second half of the intervention group (D). Except for the sham operation in group A, rats in each group underwent bilateral ovariectomy. Group C received simvastatin (5 mg/kg/d) after 10 weeks of intervention, and group D received drug treatment after 10 weeks. got canceled. I started to receive simvastatin intervention. Twenty weeks after the operation, all rats were sacrificed and the levels of serum type I collagen pro-amino-terminal propeptide (PINP) and type I collagen carboxy-terminal cross-linked terminal peptide (ICTP) were detected by enzyme-linked immunosorbent assay (ELISA). finished. , 4, 5 lumbar vertebrae, dual-energy X-ray method to detect the bone density of the 3rd lumbar vertebra in rats, compression test to detect the maximum load, elastic modulus and other biomechanical indicators of the 4th lumbar vertebrae, microcomputer tomography through rays The bone mass and microstructure of the first 5 lumbar vertebra cancellous bone detected by radiography (micro CT).

  Results: (1) Serological results: PINP and ICTP of groups B, C and D were significantly higher than those of group A; (2) Bone mineral density: group B, other groups C and D were significantly lower than group A ( P\u003c0.05); (3) Biomechanics: the maximum load and elastic modulus of group B were significantly lower than those of the other three groups (P\u003c0.05), group C and D were significantly lower than group A (P \u003c0.05); 4. Micro CT: The bone volume fraction (BV/TV) and trabecular bone (Tb).N) of group A were significantly higher than those of the other 3 groups. Trabecular bone separation (Tb.Sp) was other In the 3 groups (P\u003c0.05), the Tb.Sp of the C and D groups was significantly lower than that of the B group (P\u003c0.05).

  Conclusion: Twenty weeks after ovariectomy, rats experienced significant bone loss and bone loss. In the upper part of the intervention and the lower part of the intervention, it partially prevented the bone loss, microstructure degradation and mechanical performance of the model, but failed to restore the bone density to normal levels.