CALCIUM ION INTERACTIONS IN DEVELOPING DENTAL TISSUES

该项目的长期目标是澄清 成釉细胞的具体阶段，并确定其作用 细胞膜及其在控制 钙离子转运与矿化的关系。 动物模型 系统，包括系统和局部应用实验 药物通过手术窗对大鼠成釉细胞的影响 将被使用。 要检验的假设是：（1）特定区域的 成釉细胞膜控制钙沿着 或在膜内以及在细胞外和 细胞内区室 酶分布的变化 和其他膜成分，钙通道， 专门化，如皱褶边界;和交界 络合物在该过程中充当重要的控制机制。 (2)成熟成釉细胞的形态类型（光滑和 褶皱结束）反映了吸收途径的专业化， 搪瓷中有机元素的处理。 以下 将使用实验试剂：钙拮抗剂钴， 维拉帕米、镧和丁卡因 抑制剂槲皮素和依他尼酸;降钙素激素; 抗微管剂秋水仙碱和氟化钠。 一 多方法分析将应用于使用光和电子 显微镜、放射自显影、细胞化学和元素分析 微量分析，以确定这些代理人的影响， 将结果与假定的假设联系起来。 这些实验对于阐明生物学的基本原理具有重要意义。 参与细胞控制钙转运的机制， 成釉细胞形态类型在釉质形成中的作用 阵 这项建议的结果对以下方面有影响： 治疗和预防措施， 矿化组织

The long-range goals of this project are to clarify the functions of the specific stages of the ameloblast and to determine the roles of the cell membranes and their specializations in controlling calcium transport in relation to mineralization. An animal model system, including systemic and local application of experimental agents through surgical windows over ameloblasts in rat mandibles, will be utilized. The hypotheses to be tested are: (1) Specific regions of ameloblast cell membranes control translocation of calcium along or within the membranes and between the extracellular and intracellular compartments. Variation in distribution of enzymes and other membrane constituents, calcium channels, specializations such as the ruffled border; and junctional complexes serve as important control mechanisms in this process. (2) Morphologic types of maturation ameloblasts (smooth and ruffle-ended) reflect specializations in routes of absorption and processing of organic elements of enamel. The following experimental agents will be utilized: calcium antagonists cobalt, verapamil, lanthanum and tetracaine; Ca+2-Mg+2 ATPase inhibitors quercetin and ethacrynic acid; the hormone calcitonin; the anti-microtubular agent colchicine; and sodium fluoride. A multi-method analysis will be applied using light and electron microscopy, autoradiography, cytochemistry, and elemental microanalysis to determine the effects of these agents and to correlate the results with the postulated hypotheses. The proposed experiments are significant for clarifying the basic mechanisms involved in cellular control of calcium transport and the roles of the morphologic types of ameloblasts in enamel formation. The results of this proposal have implications for therapeutic and preventative measures against diseases involving mineralized tissues.