[Comparison of experimental models of renal ischemia. Morphologic study]

The authors investigated in rats after unilateral nephrectomy morphological changes in the remaining kidney where the blood flow was arrested for 20, 30, 45 or 60 min. The investigation period was 24 hours, 3, 7, 14, 21 and 28 days after ischaemization. After short-term ischaemia monocellular necroses of the cortex epithelium in the canals occurs and rapid regeneration. In the initial stages after 20 min. ischaemia and in all periods after 30 min. ischaemia the authors observed slight hyperplasia of the juxtaglomerular apparatus manifested by fine granulations. After ischaemia persisting for 45 min. in addition to necroses of the tubules regressive arterial changes are observed with subsequent regeneration from the deep cortex to the surface. After discontinuation of the blood flow for 60 min. the animals die after 7 days with diffuse damage of the cortical parenchyma and regression of smooth muscle cells of the arterial walls with subsequent insudates of the media.