Detection of ion shifts in proximal tubule cells of the rat kidney using x-ray microanalysis.

The present study represents an attempt to combine scanning transmissions electron microscopy and x-ray microanalysis on thin sections at the intracellular level using kidney tubules in both normal and altered conditions. The results show that semi-quantitative estimates made from X-ray microanalysis can predict the pattern of electrolyte change both in direction and degree; these estimated agree with previously determined chemical analysis of identically treated tissue. Before these promising results can be extended to quantitative intracellular compartment analysis, further work is needed in several areas including preparation of adequate standards, improved ultracryomicrotomy techniques, improvement of contrast of ultrathin frozen sections and standardization in computing background measurements.