Cellular Localization Of Gadolinium In Cardiac And Vascu

本项目的目的是利用电子探针x射线微分析和电子能量损失谱（EELS）来定位心脏和血管组织中的MRI造影剂钆。光谱成像方法的灵敏度首先通过绘制用于传递造影剂的切片聚合物颗粒中所含的螯合钆来证明。目前正在进行的实验是绘制用钆造影剂治疗的缺血和对照大鼠心脏细胞内Gd的分布。通过夹紧液氮冷却的铜表面，组织迅速冻结。然后将块转移到超低温组中，在那里它们被切割到大约100纳米的厚度，在涂有碳涂层的Formvar的铜网格上拾取，并在分析前存储。人们希望用这种方法来确定哪些亚细胞区室会积聚钆。这些标本将在配备能量色散x射线光谱仪的高分辨率STEM中进行分析。

The aim of this project is to localize the MRI contrast agent gadolinium in cardiac and vascular tissues using electron probe x-ray microanalysis and electron energy loss spectroscopy (EELS). The sensitivity of the spectroscopic imaging approach is first demonstrated by mapping chelated gadolinium contained in sectioned polymer grains that are used to deliver the contrast agent. Experiments are now being performed to map the distribution of intracellular Gd in ischemic and control rat heart that has been treated with the gadolinium contrast agent. Tissue is rapidly frozen by clamping against liquid nitrogen cooled copper surfaces. Blocks are then transferred to an ultra-cryomicrotome where they are cut to a thickness of approximately 100 nm, picked up on copper grids coated with carbon-coated Formvar, and stored prior to analysis. It is hoped to use this approach to determine which subcellular compartments accumulate gadolinium. The specimens will be analyzed in a high-resolution STEM equipped with an energy-dispersive x-ray spectrometer.