摘要
目的:探讨磁场直接提高骨密度的作用途径,从而为骨质疏松的磁疗提供科学依据。方法:实验分别于2003-12/2004-06在深圳大学生命科学学院微生物基因工程重点实验室及香港城市大学深圳研究中心细胞学实验室完成。①体内研究:选择雌性SD大鼠90只,随机分为6组,每组15只,除假手术组外另5组大鼠均切除卵巢。曝磁处理于卵巢切除2周后进行。假手术组仅手术切除卵巢附近一小块脂肪;去卵巢组仅进行卵巢切除术;去卵巢+钙组另外给予200mg/kg苏糖酸钙灌胃,1次/d;去卵巢+钙+磁30min/d组在去卵巢+钙组的基础上给予30min/d曝磁30d处理;去卵巢+磁30min/d组仅给予去卵巢大鼠30min/d曝磁30d处理;去卵巢+磁60min/d组在去卵巢+磁30min/d组基础上曝磁时间延长为60min/d,共30d。分别磁场对各组大鼠骨密度、骨强度、骨钙含量、雌二醇和骨钙素的影响。检测成骨细胞、破骨细胞的生长和功能的指标-骨碱性磷酸酶及尿脱氧吡啶交联水平。②体外研究:为进一步在细胞水平阐明磁场影响骨密度的原理,培养RAW264.7细胞株(前破骨细胞),使用破骨细胞分化因子诱导其向破骨细胞分化,同时外加磁场处理,观察磁场对RAW264.7细胞株生长、成熟情况的影响。另外在不同强度磁场下培养兔破骨细胞,观察对骨片的吸收情况。结果:纳入大鼠90只,全部进入结果分析,无脱失。①体内研究:各组大鼠骨密度及生物力学参数的变化:所有曝磁组大鼠的骨密度均高于去卵巢组,其中去卵巢+磁60min/d组大鼠显著高于去卵巢组(F=6.98,P<0.05)。各曝磁组大鼠骨碱性磷酸酶含量显著高于去卵巢组及假手术组(F=6.98,9.14,P<0.05)。各曝磁组大鼠尿脱氧吡啶交联水平显著低于去卵巢组(F=21.41,P<0.01)。②体外研究:强恒定磁场对RAW264.7细胞生长、分化和功能的影响:在磁场作用下培养的经破骨细胞分化因子诱导的RAW264.7细胞株加速凋亡,而兔破骨细胞裙边消失,吸收骨片的能力丧失。结论:旋转恒定磁场能够促进大鼠成骨细胞的生长和分泌功能、抑制破骨细胞生长和破骨功能,从而提高骨密度及骨强度,对于骨质疏松有较好的干预效果。
AIM： To explore the effect mechanism of rotary constant-strength magnetic field （RCMF） directly increased the bone density so as to provide scientific basis for magnetic field therapy for osteoporosis. METHODS： The experiment was conducted at the Key Lab of microbe and Gene Engineering, College of Lift Sciences, Shenzhen University and cell lab of Shenzhen Applied R＆D Centres of City University of Hong Kong from December 2003 to June 2004. ①Research in vivo： Ninety female SD rats were selected and assigned randomly into 6 groups with 15 rats in each group. Ovaries of the rats in the groups were cut except the sham operation group. Two weeks later, RCMF was given. A small block of fat around ovaries of rats in the sham operation group was cut out. Those in the ovariectomized group （OVX group） were treated with ovariectomy. Those in the OVX ＋Ca group were treated with 200 mg/kg Calcium L- Threonate in addition with gastric perfusion, once a day. Those in the OVX＋Ca＋RCMF 30 minutes per day group were given 30 minutes RCMF per day on the basis of that in the OVX＋Ca group for 30 days. Those in the OVX＋RCMF 30 minutes per day group were given 30 minutes RCMF per day for 30 days. Those in the OVX＋RCMF 60 minutes per day group were given 60 minutes RCMF per day on the basis of that in the OVX＋ RCMF 30 minutes per day group for 30 days. Effect of magnetic field on bone mineral density （BMD）, bone-loading forces, content of calcium, aquadiol and osteocalcin was observed. Indexes of bone-specific alkaline phosphatase （BAP） and deoxypyridinoline crosslinks （DPD） of the rats serum, which could show the growth and function of osteoblast and osteoclast were tested, ② Research in vitro＇, In order to clarify the mechanism of RCMF effect in cell level, RAW264,7 ceils were cultured in the presence of using osteoclast differentiation factor （ODF）, which could made it differentiate into osteoclastike cells, Meanwhile, magnetic field was used, and the effect of magnetic field on growth and maturity of RAW264.7 cells was observed. Besides, rabbit osteoclasts were cultured in different strength magnetic field and absorption ability of spicula was observed. RESULTS： Totally 90 included rats were involved in the result analysis, no drop-out rats.①Research in vivo： Changes of BMD and biomechanics parameters： The BMD of rats in the RCMF group was higher than that in the OVX group, in which that in the OVX＋RCMF 60 minutes per day group was higher significantly than that in the OVX group （F=6.98,P 〈 0.05）. The content of BAP of rats in the RCMF group was higher obviously than that in the OVX group and the sham operation group （F= 6.98,9.14,P 〈 0.05）. The level of DPD of rats in the RCMF was lower markedly than that in the OVX group （F=21.41 ,P〈 0.01 ）. ②Research in vitro： The effects of RCMF to growth, differentiation and function of RAW264.7 cells： The RAW264.7 cell strain induced by ODF accelerated apoptosis under magnetic field. RCMF could inhibit growth of rabbit osteoclast and absorption ability of rabbit osteoclast disappeared. CONCLUSION： RCMF can increase growth and excretory function of osteoblast and inhibit growth and function of osteoclast so as to elevate BMD and bone-loading forces, which has better interventional effect for osteoporosis.
出处
《中国临床康复》
CAS
CSCD
北大核心
2006年第5期74-77,i0004,共5页
Chinese Journal of Clinical Rehabilitation
基金
国家自然科学基金面上项目(50177018)~~
