Glomerular mesangial and endothelial cell swelling following temporary renal ischemia and its role in the no-reflow phenomenon.

The purpose of these experiments was to define changes in glomeruli of rats kidneys which could account for a marked reduction of blood flow immediately following temporary ischemia. After the renal artery had been clamped for 60 minutes, mesangial and endothelial cellular swelling was sufficiently severe to compress and trap intracapillary erythrocytes, obstruct capillary lumens, and prevent reflow of an isotonic carbon suspension. Perfusion of saline solution before the renal arteries were clamped washed blood from the kidney, and the resulting cellular swelling alone was not sufficient to block capillary lumens. Erythrocyte trapping did not occur after 15 minutes of ischemia. Swelling of glomerular and tubular epithelial cells produced some extrinsic capillary compression that could contribute to erythrocyte trapping, but this appeared to be of minor importance in producing the no-reflow phenomenon.