CELL EXCITABILITY MECHANISMS OF ELECTROMAGNETIC FIELDS

描述：（改编自申请人的摘要）：公众的关注， 有人提出电力线（60赫兹）可能产生的不利影响 电磁场（EMF）对神经系统的影响 我们的研究将 通过查明和审查 电磁场在细胞、亚细胞和分子水平上影响神经细胞 从而改变关键的细胞功能。 离体肾上腺嗜铬细胞 将用作交感神经系统功能的体外模型， 这些研究。 在初步实验中，将嗜铬细胞暴露于磁场中， 在0.8 - 1.4毫特斯拉（mT）范围内的通量密度导致了 细胞内钙和刺激儿茶酚胺释放。 这些 电磁感应效应将在拟议的研究中进一步调查。 研究将采用荧光钙成像技术和45 Ca 2 + 吸收测量，以阐明EMF诱导的 细胞内钙离子增加。 这两种方法，在 结合高效液相色谱法测定儿茶酚胺 色谱法（HPLC），将用于确定长期影响 电磁场对儿茶酚胺释放及生物合成速率的影响 将被确定。 这些研究将采用HPLC和放射性同位素 评价细胞内儿茶酚胺水平的标记方法及其应用 前体，原位和体外测定，以评估 儿茶酚胺生物合成酶及分子生物学技术研究 酪氨酸羟化酶表达水平的变化， 催化儿茶酚胺生物合成途径中的限速步骤。 提出的研究的长远意义是重要的 将获得的关于电磁场对细胞影响的信息， 神经细胞 这些信息对于评估潜在的 与EMF暴露相关的健康风险，以及帮助我们 了解使用EMF的潜在治疗策略。

DESCRIPTION: (Adapted from the applicant's abstract): Public concern has been raised about possible adverse effects of powerline (60-Hertz) electromagnetic fields (EMFs) on the nervous system. Our research will address this question by identifying and examining the mechanisms by which EMFs effect neural cells at the cellular, subcellular and molecular levels and thus alter key cellular functions. Isolated adrenal chromaffin cells will be used as an in vitro model of sympathetic nervous system function for these studies. In preliminary experiments, exposing chromaffin to magnetic flux densities in the 0.8 - 1.4 millitesla (mT) range caused both a rise in intracellular calcium and a stimulation catecholamine release. These EMF-induced effects will be further investigated in the proposed research. Studies will employ fluorescence calcium imaging techniques and 45Ca2+ uptake measurements to elucidate the mechanisms that underlie EMF-induced increases in intracellular calcium. These same two methodologies, in conjunction with assay of catecholamines by high performance liquid chromatography (HPLC), will be used to establish the long-term effects of EMFs on catecholamine release as well as catecholamine biosynthesis rates will be determined. These studies will employ HPLC and radioisotopic labeling methods to assess intracellular levels of catecholamines and their precursors, in situ and in vitro assays to assess alterations in activity of catecholamine biosynthetic enzymes and molecular biology techniques to study changes in the level of expression of tyrosine hydroxylase, the enzyme that catalyzes the rate-limiting step in the catecholamine biosynthetic pathway. The long-term significance of the proposed research is the important information that will be obtained regarding cellular effects of EMFs on neural cells. Such information will be essential for evaluating potential health risks associated with EMF exposure, as well as aiding our understanding of potential therapeutic strategies employing EMFs.