Selective intracellular beryllium localization in rat tissue by mass-resolved ion microprobe imaging.

Beryllium absorption sites in the kidney and liver of rats have been located and imaged at approximately 70 nm lateral resolution with a scanning ion microprobe utilizing secondary ion mass spectrometry. Embedded sections and lyophilized cryosections of these organs were prepared after in vivo administration of beryllium in soluble form. Beryllium distribution images were correlated with the histological microstructure revealed by CN- images. In the kidney, beryllium concentrates selectively within the nuclei of proximal tubule cells and occasionally within modified podocytes or mesangial cells in the glomerulus. In the liver, beryllium is seen to localize within severely altered lysosomal structures as well as within hepatocyte nuclei. These observations are relevant to understanding aspects of the toxic and carcinogenic properties of absorbed beryllium compounds.