ELECTRIC FIELD ATTENUATION OF OSTEOCLAST FORMATION

调节刺激骨吸收的全身激素信号 根据当地的具体情况。 最重要的 骨骼稳态的局部调节剂是物理刺激。 一 骨对负荷的反应的建议机制是局部的 机械刺激会产生电场， 骨组织作为骨调节。 实际上，时变电场 已成功用于预防动物废用性骨质疏松症。 因此，我们假设破骨细胞的形成， 骨吸收的细胞效应器，由局部电调节， 领域 在初步工作中，使用独特的电磁系统 能够在体外诱导均匀和可量化的电场， 我们已经表明，随时间变化的电场衰减 1，25（OH）2D诱导小鼠破骨细胞样细胞的形成 骨髓培养系统 我们建议扩展这些观察， 确定负责以下方面的当地领域的特点： 破骨细胞生成的衰减，并研究 骨吸收的激素调节剂领域。 在这项为期四年的研究中， 提出了一种方法，该方法涉及在招募过程中施加电场， 来自鼠骨髓模型系统的破骨细胞。1，25（OH）二维驱动 破骨细胞形成将通过计数破骨细胞样 细胞并在8天培养期后测定TRAP含量/孔。 将平板接种在方孔培养皿中的细胞置于实验室中。 通过产生时变磁场感应的电场 在螺线管线圈内。 将对假暴露细胞进行 接收电磁线圈内的类似振动和热变化 一个恒定的电流，它会产生一个零磁场。 我们 将研究电场的哪些成分负责 破骨细胞形成的抑制，测试频率和强度 特性以及每天所需的小时数， 最大衰减 电场的能力（使用最多的 有效场）抑制骨髓细胞集落增殖 在半固体培养基中由M-CSF、GM-CSF或IL-3支持， 检查，以表明在招聘过程中， 调节破骨细胞的形成。 然后我们将检查 这些领域，以减弱招募破骨细胞的因素， （除1，25（OH）2D外）已知在破骨细胞中重要 分化：M-CSF、GM-CSF和IL-6。 减少场效应 还将研究这些因子的骨髓培养分泌 使用标准生物测定来评估田间处理的培养基。 这些实验应该提供对正常位点的独特见解 具体控制骨转换。此外，通过识别这些 电场调节破骨细胞的形成，一种新的 局部治疗高风险区域的治疗方案 退化性骨质流失成为可能。

Systemic hormonal signals which stimulate bone resorption are modulated in a site specific manner by local factors. Among the most important local regulators of skeletal homeostasis are physical stimuli. One proposed mechanism for the response of bone to loading is that local mechanical stimuli generate an electric field which can be sensed by bone tissue as osteoregulatory. Indeed, time varying electric fields have been used with success to prevent disuse osteoporosis in animals. Therefore, we have hypothesized that the formation of osteoclasts, the cell effectors of bone resorption, is modulated by the local electric field. In preliminary work, using a unique electromagnetic system capable of inducing uniform and quantifiable electric fields in vitro, we have shown that time varying electric fields attenuate the 1,25(OH)2D-driven formation of osteoclast-like cells from the murine marrow culture system. We propose to extend these observations, defining the characteristics of the local field responsible for attenuation of osteoclastogenesis, and investigating interactions of the field with hormone regulators of bone resorption. In this four year study a systematic series of in vitro experiments is proposed which involves applying electric fields during recruitment of osteoclasts from the murine marrow model system. 1,25(OH)2D-driven osteoclast formation will be assessed by counting of osteoclast-like cells and assay of TRAP content/well after an 8 day culture period. Cells plated in square well dishes will be placed within experimental electric fields induced by creating a time varying magnetic field within a solenoid coil. Sham exposed cells will be subjected to similar vibrational and thermal variations within a solenoid receiving a constant electric current, which induces a null magnetic field. We will examine which components of the electric field are responsible for inhibition of osteoclast formation, testing frequency and intensity characteristics as well as the number of hours per day required for maximal attenuation. The ability of electric fields (using the most efficacious field) to inhibit marrow cell colony proliferation supported by M-CSF, GM-CSF or IL-3 in semisolid media will then be examined to indicate at which point during recruitment the field modulates osteoclast formation. We will then examine the ability of these fields to attenuate the recruitment of osteoclasts by factors (besides 1,25(OH)2D) known to be important in osteoclast differentiation: M-CSF, GM-CSF and IL-6. Field effects to diminish secretion by the marrow culture of these factors will also be studied using standard bioassays to assess field treated media. These experiments should provide unique insights into the normal, site specific control of bone turnover. Further, by identifying those electric fields which modulate osteoclast formation, a novel therapeutic regimen for the local treatment of areas at high risk of involutional bone loss becomes possible.