PROCESSES OF METAL SELECTION BY METAL ACCUMULATING CELLS

该项目的目的是确定和表征 使海洋中的孔细胞 前鳃腹足类滨螺（Littorina littorea） 积累铜优先于其他生物可利用的金属。 一 设计了一系列实验来证明， 这些细胞从血液中积累金属， 观察到的细胞在体内显示的选择性是由于：（1） 这种特定细胞类型所特有的内在特性;（2） 其他细胞类型如嗜碱性细胞的活性， 从血液中除去铜以外的金属;（3）体液 与Cu结合并同时将金属引导至 细胞并促进其吸收。 一些技术，包括 细胞培养，能量色散X射线微区分析，放射性 分析，凝胶电泳，尺寸排阻高效 液相色谱-电感耦合等离子体质谱 光谱法将被用来解决的相对重要性， 上述三个因素。 短期动力学研究将 也可以用来确定细胞对Cu的吸收是否 载体介导的。 与其他药物的竞争性抑制研究 金属将被用来确定吸收的特异性 系统和运输系统的能量要求 还将使用各种代谢抑制剂进行研究。 在 结合，这些研究将提供一个机制 理解允许顺序的过程 识别、选择和引导金属到特定细胞 在高等真核生物中。 从长远来看，这些研究将 也有助于开发铜基杀螺剂，以控制 腹足类双脐螺传播血吸虫病 光滑的 最后，这些研究代表了第一次尝试， 定量研究细胞中铜的通量和周转， 电感耦合等离子体~（63）Cu稳定同位素分析 质谱分析法来 因此，这项技术提供了一种新的 方法学与健康相关科学的研究， 重要但可能有毒的元素

The purpose of this project is to identify and characterize the mechanisms which enable the pore cells of the marine prosobranch gastropod Littorina littorea to specifically accumulate Cu in preference to other bioavailable metals. A series of experiments have been designed to demonstrate that these cells accumulate metals from the blood and to test if the observed selectivity shown by the cells in vivo is due to: (1) intrinsic properties unique to this particular cell type; (2) the activities of other cell types such as the basophil cells in the removal of metals other than Cu from the blood; (3) humoral factors which bind to Cu and act to both vector the metal to the cell and facilitate its uptake. A number of techniques including cell culture, energy dispersive X-ray microanalysis, radiometric analysis, gel electrophoresis, size exclusion high performance liquid chromatography and inductively coupled plasma mass spectrometry will be used to resolve the relative importance of the three factors outlined above. Short term kinetic studies will also be undertaken to determine if Cu uptake by the cells is carrier mediated. Competitive inhibition studies with other metals will be used to determine the specificity of the uptake system and the energetic requirements of the transport system will also be studied using various metabolic inhibitors. In combination, these studies will provide a mechanistic understanding of the processes which permit the sequential recognition, selection and vectoring of metals to specific cell types in higher eukaryotes. In the long term, these studies will also help in the development of Cu based molluscicides to control the spread of schistosomiasis by the gastropod Biomphalaria glabrata. Finally, these studies represent the first attempt to study the flux and turnover of Cu in cells quantitatively using stable isotopic analysis of 63Cu by inductively coupled plasma mass spectrometry. This technique therefore offers a new methodology to the health related sciences for the study of this essential, but potentially toxic element.