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内容記述 |
The kidney is important for the disposition of heavy metals taken into the body, and the renal proximal tubules are responsible for the region-specific reabsorption of substances from the urine. The dynamics of elemental distribution in the renal tubules, however, has not been clearly understood. In the present study, the precise distribution of endogenous elements, such as phosphorus (P) and potassium (K) in the kidney with distinguished tubular regions was examined in mice administered to renal tubular invasion heavy metals, such as platinum (Pt) or cadmium (Cd), by micro-PIXE (particle induced X-ray emission) analysis. Renal cryo-sections (thickness, 10 μm) were subjected to micro-PIXE analysis. Areas of concentrated P and K were observed in the outer stripes of the outer medulla, where the distal portion of the proximal tubules were distributed, after Cd administration, but not Pt. The dynamics of Pt and Cd distribution were also examined by high-energy SR-XRF (X-ray fluorescence analysis using high energy synchrotron radiation) using serial sections of micro-PIXE specimens. Correlating the distribution of P and K with the distribution of heavy metals, Cd, which caused the formation of P and K concentrations, had a localized distribution in the renal tubular epithelium, whereas Pt, which did not cause P and K concentrations, was uniformly distributed, with no localization-like distribution. The combined micro-PIXE and SR-XRF technique can be a powerful method for studying element distribution dynamics in the renal tubules. |
