Quantitative EPXMA imaging of rapidly frozen kidney proximal tubule primary cultures
Understanding the role of elements/ions (particularly calcium) in processes such as cellular injury in the kidney requires not only assessment of total cell element and its cytoplasmic free ion, but also identification of the sites of release, uptake and binding of those ions/elements within the cells and correlation with physiological lesions such as changes in cell metabolism. Short term anoxia (40min) does not appear to alter Ca compartmentation in kidney proximal tubule cells. However, the effects of longer periods of anoxia and subsequent recovery have not been studied due to the lack of a suitable in vitro model. Quantitative electron probe x ray (EPXMA) imaging facilitates assessment of cell ultrastructure and measurement of total element with high lateral spatial resolution. We have therefore applied EPXMA imaging to a recently described preparation of primary kidney proximal tubule cultures, which retain the in vivo metabolic features of proximal tubules for longer periods of time in vitro.