FREQUENT APOPTOSIS IN HUMAN KIDNEYS AFTER ACUTE RENAL HYPOPERFUSION

Background/Aims: Apoptosis, a form of cell death characterized by DNA fragmentation and minimal inflammation, is induced by intrarenal hypox ia in rats. The objective of this study was to test whether apoptosis participates in human acute renal injury. Methods: We examined kidneys obtained from autopsies of 40 patients following hemodynamic compromi se and from 9 controls following sudden death. Nuclear DNA fragmentati on was assayed by in situ 3' end labeling (TUNEL stain) and compared t o histological findings. Results: DNA fragmentation along renal tubula r cells was observed in 23 (57%) of the study patients but in none of the controls (p < 0.005). Acute tubular necrosis was seen by formal hi stology in 27% of the patients and correlated with clinical acute rena l dysfunction, while DNA fragmentation did not. Conclusion: DNA fragme ntation often occurs after renal hypoperfusion and does not imply rena l failure. Apoptosis may participate in the adaptive response of the k idney to hypoxia.