低频脉冲电磁场对去势骨质疏松大鼠腰椎骨形态计量学的影响

目的观察低频脉冲电磁场(pulsed electromagnetic fields,PEMFs)对去势骨质疏松(osteoporosis,OP)大鼠腰椎骨组织形态计量学的影响,探讨PEMFs治疗OP的作用机制。方法将66只3月龄雌性SD大鼠随机分为假手术组(A组,n=12)、PEMFs实验组(B组,n=12)、雌激素对照组(C组,n=12)、卵巢切除对照组(D组,n=30)。A组大鼠仅切除卵巢周围部分脂肪组织,不切除卵巢;其余各组大鼠均切除双侧卵巢,制备去势OP大鼠模型。术后12周,B组采用低频PEMFs(8 Hz、3.8 mT、40 min/d)干预治疗30 d;C组采用倍美力0.065 mg/(kg.d)灌胃30 d;A、D组正常饲养。观察各组大鼠一般情况,术后12周检测血清雌二醇水平;干预治疗30 d后处死大鼠,取L4椎体作组织学切片,行静态骨形态计量学分析。结果术后D组大鼠毛发逐渐稀疏,活动迟缓,精神不振,反应较迟钝;A、B、C组大鼠毛发均光洁,精神及活动正常。术后12周,A组和D组大鼠血清雌二醇水平分别为(54.93±23.52)pg/mL和(31.99±23.45)pg/mL,比较差异有统计学意义(t=2.345,P=0.029)。干预治疗30 d后HE染色观察示,D组骨质变薄,骨髓扩大,骨小梁分布稀疏并变细,见断裂现象;A、B、C组骨小梁粗细一致,分布均匀,无断裂现象。B组大鼠L4椎体骨小梁面积百分比显著高于D组(P<0.05),也高于A、C组,但差异无统计学意义(P>0.05);骨小梁厚度显著高于D组(P<0.05),低于A、C组,但差异无统计学意义(P>0.05);骨小梁数量显著低于D组(P<0.05),高于A、C组,但差异无统计学意义(P>0.05);骨小梁分离度高于D组,低于A、C组,差异均无统计学意义(P>0.05)。结论 8 Hz、3.8 mT的PEMFs干预30 d可有效改善去势OP大鼠骨显微结构,增加骨小梁面积百分比、骨小梁厚度,降低骨小梁数量,对大鼠OP有良好的防治作用。

Effect of low frequency pulsed electromagnetic fields on lumbar bone histomorphometry in ovariectomized osteoporosis rats

Objective To investigate the changes of lumbar bone histomorphometry after exposure to low frequency pulsed electromagnetic fields(PEMFs),and to further understand the effect of PEMFs on osteoporosis(OP) in ovariectomized OP rats.Methods Sixty-six 3-month-old Sprague Dawley rats were randomly divided into 4 groups: group A(n=12),group B(n=12),group C(n=12),and group D(n=30).In group A,the ovaries were not resected as sham-ovariectomy;in groups B,C,and D,the ovaries were resected.At 12 weeks after ovariectom...