Scanning electron microscopy of the ischaemic kidney--changes in the surface microstructure of glomerular epithelial cells.
Domestic rabbits were used to study the changes that occur during ischaemic conditions in the kidney. With a scanning electron microscope, the microcellular changes at the surface of gomerular epithelial cells were observed regularly from the onset of ischaemia until five hours later. After one hour of ischaemia, the surface of the glomerular epithelial cells showed mild swelling and some change in its smooth appearance. One part had taken on a sponge-like appearance. After 2.5 hours of ischaemia, the epithelial cells had atrophied and the entire cell surface was clearly sponge-like. It was no longer possible to distinguish the small pore-like structures that had been seen on the cell surface in the normal. Moreover, 2.5 hours of ischaemia was the time when, biochemically, cell metabolism had completely ceased and the permeability of the cell membrane had altered. The cell was considered to have undergone irreversible change by this stage. After 5 hours of ischaemia, cells were markedly atrophied and the appearance of the surface had become even more sponge-like.