Biomechanics research on ATP6i gene-interference treating steroid-induced necrosis of the femoral heads in rats / 中华骨科杂志

ABSTRACT

Objective To explore the biomechanics mechanism of ATP6i gene-interference treating steroid-induced necrosis of the femoral heads(SINFH)in rats.Methods Forty SD rats were randomly assigned to four groups:blank control group,experimental control group,ATP6i SiRNA(+)group and ATP6i SiRNA(-)group,10 rats in each group.We established rat models of SINFH by injecting Escherichia Coli Endotoxin and prednisolone for 12 weeks,then cut along the inner side of the patella for about 1 cm and turn the patellar outside of the both knees of the experimental control group,the ATP6i SiRNA(+)group and the ATP6i SiRNA(-)group,and drill from the intercondylar until the femoral neck.Rats were treated by transfecting ATP6i small interference RNA(ATP6i SiRNA)into the osteoclasts of the femoral heads to interference the expression of ATP6i SiRNA(+),or by the ATP6i SiRNA(-)and same amount of saline.One month later,test the load,stress,modulus of elasticity,and axial stiffness of the right femoral heads of all four groups,and at the same time take the left femoral heads of all four groups for pathological study.Results The load,stress,modulus of elasticity,and axial stiffness of the ATP6i SiRNA(+)group were(307.01±27.34)N,(60.44±5.38)MPa,(125.29±11.16)MPa,(162.42±14.45)N/mm,respectively,which were much greater than the ATP6i SiRNA(-)group and the experimental control group(P＜0.05).In the pathological studies,we found that the trabecula of the femoral heads of the ATP6i SiRNA(+)group was much thicker than the ATP6i SiRNA(-)group and the experimental control group,but the degeneration,necrosis and breakage of the osteoepiphysis in each group had no statistically significant differences.Conclusion ATP6i gene-interference can inhibit the acid-secreting function of osteoclasts and improve the biomechanical property of the femoral heads of rats in treating the SINFH.