雌激素干预骨质疏松大鼠牙槽骨改建过程中白细胞介素1的表达

Estrogen effects on interleukin-1 expression in alveolar bone remodeling of osteoporotic rats

背景:目前大鼠是骨质疏松研究中使用最多的模型动物,其中大鼠去卵巢动物模型应用最广泛,雌性大鼠在卵巢切除后,其骨质变化和给予雌激素后的反应与人相似。目的:建立骨质疏松拔牙创愈合的大鼠动物模型,研究雌激素应用对骨质疏松大鼠牙槽骨中白细胞介素1分布及表达的影响。方法:选用65只纯种3月龄雌性大鼠,按随机数字表法分为2组,骨质疏松模型组40只大鼠在全麻下摘除双侧卵巢,25只假手术组摘除卵巢周围与之大小相同的脂肪组织,常规饲养8周以建立大鼠骨质疏松模型。造模成功后全麻拔除大鼠左侧上颌磨牙,病理彩色图像分析仪分析颌骨变化。在骨质疏松模型组中随机抽取15只皮下注射苯甲酸雌二醇作为雌激素治疗组。免疫组织化学法观察白细胞介素1在各组大鼠拔牙后牙槽骨改建过程中的表达变化。结果与结论:卵巢切除后,骨质疏松模型组大鼠的骨小梁薄而少,骨小梁间距变宽,颌骨骨强度下降。应用雌激素治疗后,发现雌激素治疗组白细胞介素1的阳性表达较骨质疏松组减少。提示3月龄SD雌性大鼠去卵巢8周后可发生骨质疏松,雌激素治疗对骨质疏松大鼠拔牙创骨愈合牙槽骨中白细胞介素1表达有明显的抑制作用。

BACKGROUND： Currently rats are the most frequently used animal for the models of osteoporosis and ovariectomized rat models have been widely applied due to ovariectomized female rats are similar to human body in bone mineral density changes and response after estrogen administration. OBJECTIVE： To establish rat models of osteoporotic tooth extraction wound healing, and to investigate the effect of estrogen on the interleukin-1 expression and distribution in the remodeling of osteoporotic alveolar bone. METHODS： Sixty-five purebred female rats, 3 months old, were randomly divided into two groups： osteoporosis model group （n=40; ovariectomy under general anesthesia） and sham operation group （n=25; fat tissue around ovary was removed）. After 8-week feeding, osteoporosis models were established and the left upper molar was pulled out under general anesthesia. Histomorphomeric parameters test was performed on the jaw bone. In osteoporosis model group, 15 rats were randomly selected to give subcutaneous injection of estradiol benzoate, as the estrogen treatment group. Immunohistochemical method was applied to observe the interleukin-1 e^pression in the remodeling of osteoporotic alveolar bone. RESULTS AND CONCLUSION： After ovariotomy, the amount of trabecula decreased and the medullary cavity ofthe bone became larger, the jaw bone intensity decreased. After administration of estrogen, the positive expression of interleukin-1 was reduced as compared with osteoporosis model group. Experimental findings indicate that, osteoporosis can be detected in Sprague-Dawley female rats aged 3 months at 8 weeks after ovariotomy, and administration of estrogen can obviously decrease interleukin-1 positive expression in the remodeling of osteoporotic alveolar bone.