Mizuhira V, Hasegawa H, Notoya M
Medical Research Institute, Tokyo Medical University, Japan.
J Neurosci Methods. 1994 Dec;55(2):125-36. doi: 10.1016/0165-0270(94)90205-4.
The distribution of Ca2+ ions is demonstrated in the synaptic terminals by means of a 2-step chemical precipitation of Ca2+ ions in nervous tissue. K-oxalate/K-antimonate chemical replacement with simultaneous computerized microwave irradiation is used. This precipitate in cell structures was investigated by computerized electron probe X-ray micro-analysis. The calculated values (from the theoretical, standards and sections), elemental binding ratios and elemental molecular weight ratios were compared. Each calculated value coincided with the theoretical value. This method can reliably detect Ca2+ ions at the micromolar level. Ca2+ ions were distributed in the synaptic vesicles and surrounding membranes. Further progress is expected in freeze-substitution and in the application and propagation of the EELS-Imaging system in calcium determinations.
通过在神经组织中对Ca2+离子进行两步化学沉淀的方法，在突触终末展示了Ca2+离子的分布情况。采用草酸钾/锑酸钾化学置换并同时进行计算机控制的微波辐照。通过计算机控制的电子探针X射线微分析研究细胞结构中的这种沉淀物。比较了计算值（来自理论值、标准值和切片）、元素结合比和元素分子量比。每个计算值都与理论值相符。该方法能够可靠地检测微摩尔水平的Ca2+离子。Ca2+离子分布于突触小泡及其周围膜中。在冷冻置换以及电子能量损失谱成像系统在钙测定中的应用和推广方面有望取得进一步进展。
