BONE CELL CALCIUM REGULATION

骨细胞钙调节

• 批准号: 3155290
• 负责人: ROSEMARY Mary DZIAK
• 金额: $ 18.52万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-04-01 至 1994-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3155290
• 关键词: DNA replication; arachidonate; bone metabolism disorder; calcium metabolism; electrophysiology; epidermal growth factor; fluorescence; fluorouracil; high performance liquid chromatography; homeostasis; hormone regulation /control mechanism; human tissue; infant animal; interleukin 1; laboratory rat; mitogens; osteoblasts; parathyroid hormones; phosphatidylinositols; plasminogen activator; prostaglandin E; prostaglandin endoperoxide synthase; protein tyrosine kinase; thin layer chromatography; tissue /cell culture; voltage /patch clamp

The long-term objective of this study Is to understand the factors regulating osteoblastic cell calcium. It is becoming increasingly evident that changes In this ion are involved in the mechanism of action of several resorptive agents and that an understanding of the various calcium regulatory systems will aid in the development of potential ways to control pathological changes in bone metabolism occurring systemically or locally. Specifically, it is proposed in osteoblastic cells isolated from the calvaria of newborn rats and In the osteoblastic human osteosarcomal cell lines, SaOS-2 and G292, to: 1. to further study the nature of the regulation of mobilization of calcium from intracellular pools with particular emphasis on the role of guanine trisphosphate and Its possible interaction with inositol phosphates such as 1(1,4,5)p3; 2. to delineate the nature of regulation of phosphoinositide metabolism and cytosolic calcium levels by the bone resorptive agent and mitogen, epidermal growth factor (EGF), in order to better compare and contrast its effects with other bone resorptive agents such as thrombin; 3. to delineate the nature of regulation of phosphoinositide metabolism by calcium via experimentation with calcium channel antagonists, an ionophore and extracellular calcium levels; 4. to study the electrophysiological properties of these cells with emphasis on membrane potential and potassium, sodium and calcium currents; 5. to study the effects of EGF and thrombin on these electrophysiological properties; 6. to study the effects of inositol phosphates on the electrophysiological properties defined in aims 4 & 5; 7. to study the role of tyrosine kinase activity in the regulation of osteoblastic cell calcium, phosphoinositide metabolism as well as proliferation In response to EGF. Cytosolic calcium regulation will be studied with the fluorescent dye, Fura-2, and phosphoinositide metabolism in tritiated -inositol labelled cells by means of high performance liquid chromatography. Cell proliferation will be assessed by incorporation of tritiated thymidine. The electrophysiological properties will be studied with patch-clamp techniques. In general, the studies proposed here should provide more In depth information on the intracellular and plasma membrane regulatory mechanisms involved in the control of osteoblastic cell calcium with emphasis. on the possible diversities of these pathways involved upon activation by agents as potentially different as EGF and thrombin.

这项研究的长期目标是了解影响因素 调节成骨细胞钙。 它正变得越来越 显然，该离子的变化与作用机制有关 几种再吸收剂的研究以及对各种吸收剂的了解 钙调节系统将有助于开发潜在的方法 控制全身发生的骨代谢病理变化 或本地。 具体来说，建议在分离的成骨细胞中 来自新生大鼠的颅骨和人类成骨细胞 骨肉瘤细胞系 SaOS-2 和 G292，目的： 1. 进一步研究 细胞内钙动员调节的性质 特别强调三磷酸鸟嘌呤的作用和 它可能与肌醇磷酸酯如 1(1,4,5)p3 发生相互作用； 2. 描述磷酸肌醇代谢调节的本质和 骨吸收剂和促细胞分裂剂的胞质钙水平， 表皮生长因子（EGF），以便更好地比较和对比 其与其他骨吸收剂（例如凝血酶）的作用； 3. 到 描述磷酸肌醇代谢调节的本质 通过钙通道拮抗剂实验来补充钙 离子载体和细胞外钙水平； 4. 学习 这些细胞的电生理特性，重点是膜 电位以及钾、钠和钙电流； 5. 学习 EGF 和凝血酶对这些电生理特性的影响； 6. 研究磷酸肌醇对电生理的影响 目标 4 和 5 中定义的属性； 7.研究酪氨酸激酶的作用 调节成骨细胞钙、磷酸肌醇的活性 代谢和增殖对 EGF 的反应。 胞质 将使用荧光染料 Fura-2 和 氚化肌醇标记细胞中的磷酸肌醇代谢 高效液相色谱法。细胞增殖会 通过掺入氚化胸苷来评估。 这 将用膜片钳研究电生理特性 技术。 总的来说，这里提出的研究应该提供更多的信息 有关细胞内和质膜调节的深度信息 成骨细胞钙控制的机制 强调。关于这些途径可能存在的多样性 由 EGF 和凝血酶等潜在不同的物质激活。