NORMAL & PATHOLOGICAL ENAMEL MINERALIZATION

我们理解正常和病理性牙釉质的长期策略 成矿作用是确定：a)降水的驱动力 钙磷酸盐在成釉过程中的作用，b)细胞在 建立这样的驱动力，以及c)可能的监管 基质-矿物相互作用的釉质形成机理(S)。 所获得的信息将应用于病理学研究。 不同氟化物作用下动物模型(小型猪和大鼠)的成釉作用 政权。 本提案包括以下具体方面：1) 从单个动物的分泌牙釉质中分离液体相 (小型猪)，其离子组成的测定及其变化 由病原体(氟化物)诱发。微生物的微体积分析 流体将通过使用离子色谱和显微分析进行。 电极。2)液体中钙结合配体的鉴定。 液体中的蛋白质成分将通过微透析分离， 电泳法和层析法。钙离子结合特性的研究 分离的流体成分将通过使用离子- 特定电极、~(45)Ca放射自显影和流速透析。基座 根据上述结果，我们将重新评估中国石油天然气的饱和程度 关于牙釉质和其他磷酸钙的釉质液体 利息。3)釉原蛋白和釉质蛋白性质的研究 猪和小鼠模型，以及它们的原位降解。这个 所涉及的性质是：a)它们在磷灰石上的选择性吸附 表面，b)它们在生理水溶液中的溶解度，以及c) 它们的疏水/亲水性质。4)吸附机理 分泌的釉原蛋白在磷灰石表面。选择性吸附 釉原蛋白的含量将与特定片段在 N-末端和C-末端，两者在矩阵中具有很高的同源性 哺乳动物牙釉质的蛋白质。此外，我们亦会努力确定 链段对溶液和固体中分子构象的影响 表面。5)基质矿物功能方面的研究 牙釉质矿化中的相互作用。人们的兴趣将集中在 磷灰石晶体蛋白质涂层对(A)掺入的影响 溶液中的离子(钙、磷和氟化物)进入晶体 (B)类流体环境中的沉淀动力学；和(C) 生长晶体的聚集和形态。

Our long-term strategy for understanding normal and pathological enamel mineralization is to determine: a) the driving force for precipitation of calcium phosphate salts during amelogenesis, b) the cellular role in establishing such a driving force, and c) the possible regulatory mechanism(s) of amelogenesis related to the matrix-mineral interaction. The information obtained will be applied to the study of pathological amelogenesis using animal models (minipigs and rats) under various fluoride regimes. The present proposal includes the following specific aspects: 1) Separation of the fluid phase from the secretory enamel of a single animal (minipig), determination of its ionic composition, and changes in it induced by pathological agents (fluoride). Analyses of micro volumes of the fluid will be conducted by the use of ion chromatography and micro- electrodes. 2) Identification of the calcium-binding ligands in the fluid. The protein constituents in the fluid will be separated by microdialysis, electrophoresis, and chromatography. The calcium-binding properties of the separated fluid constituents will be determined through the use of ion- specific electrodes, 45Ca autoradiography, and flow-rate dialysis. Based on the foregoing results, we will re-evaluate the degree of saturation of enamel fluid with respect to enamel and other calcium phosphates of interest. 3) Investigation of the properties of amelogenins and enamelins of porcine and murine models, and their degradation in situ. The properties concerned are: a) their selective adsorption onto apatitic surfaces, b) their solubility in physiologic aqueous solutions, and c) their hydrophobic/hydrophilic nature. 4) The mechanism of adsorption of the secreted amelogenin onto apatitic surfaces. The selective adsorption of the amelogenin will be related to the presence of specific segments at the N- and C-terminals, both of which have a high homology in the matrix proteins of mammal enamel. Efforts will also be made to ascertain the effect of segments on the molecular conformation in solutions and on solid surfaces. 5) Investigation of the functional aspects of the matrix-mineral interaction in enamel mineralization. Interest will be focused on the effects of protein coatings of apatite crystals on (a) the incorporation of ions (calcium, phosphate, and fluoride) from solutions onto the crystal surfaces, (b) kinetics of precipitation in fluid-like environments, and (c) the aggregation and morphology of growing crystals.