大剂量γ射线致兔股骨头坏死的病理改变

Pathological changes of ^(60)Co γ-induced osteonecrosis of femoral head in rabbits

目的观察大剂量γ射线局部照射兔股骨头后的坏死改变。方法成年雄性兔5只,分别单次接受0(1只)、30(2只)、45(2只)Gy60Coγ射线照射,6wk后取股骨头石蜡切片光境观察,体外培养骨髓间充质干细胞(BMSCs),成骨细胞诱导后,单核细胞直接细胞毒性测定法(MTT)测定其生长曲线。结果照射组兔股骨头空陷窝增加,以软骨下区最显著,骨小梁面积减少,脂肪细胞面积减少,与0Gy照射兔比较差异显著(P<0.001),照射后BMSCs成骨增殖能力与0Gy组相比明显降低(P<0.01)。结论表明30~45Gy60Coγ射线照射一次可致兔股骨头坏死改变。

Purpose To establish a ^60Co γ-radiation induced osteonecrosis model of the femoral head （ONFH） in rabbits and to observe the pathological changes of ONFH. Methods Five young rabbits were used and irradiation （0,30,45 Gy） wasapplied to the area of the head of the right femur. The femoral heads were observed by light microscope and image analysis six weeks after irradiation. BMSCs were harvested, then the grow curve were made by MTT. Results Pathological changes of osteonecrosis were found in femoral heads of irradiated rabbits, especially in the inferior surface of cartilages, the ossification ability of BMSCs was lower than that of the 0 Gy group （P〈0.01）. Conclusions Pathological changes of ONFH can be induced by single dose of 30 - 45 Gy ^60Co γ irradiation in rabbits.