Ultrastructural changes of the renal cortex after septic shock in rats

The purpose of this study was to observe the ultrastructural changes of the renal cortex that occur in septic shock. Twenty male Wistar rats were used. They were divided into 4 groups of five animals each one. A septic shock was caused by intraperitoneal injection of 5 x 10(6) living E. Coli, in a dose of 2ml/100gr B. W., in four rats of each group. The fifth rat of each group was used as control, and was injected by an equal volume of normal saline. A small segment from the right kidney was excised from every rat of each group, respectively 1, 2, 4 and 6 hours after the onset of the shock. Morphologically, alterations of the endothelium of the peritubular and glomerular capillaries were found. The endothelial layer was thick with many cytoplasmic folds. In the glomeruli, the basal lamina as well as the overlying epithelial podocytes and their foot processes were swollen. The urinary space contained erythrocytes and cell debris. Lesions of the proximal and distal tubule epithelium were also observed. The basal infoldings of the cell membrane disappeared in many epithelial cells of the proximal tubule and the brush border showed varying degrees of disruption. Within the tubular lumen much cellular debris was found. The epithelium of the distal tubule was thinner in some portions and in others it was swollen. The lesions were focal during the first hour after the onset of shock, while at the fourth and sixth hours they were most extensive. In conclusion, the ultrastructural findings after septic shock were non-specific and indicated cellular injury.