UNINEPHRECTOMY REDUCES APOPTOTIC CELL-DEATH AND ENHANCES RENAL TUBULAR CELL REGENERATION IN ISCHEMIC ARF IN RATS

Contralateral uninephrectomy attenuates unilateral ischemic renal inju ry functionally and morphologically. In this study we investigated the effects of uninephrectomy on apoptotic renal cell death and tubular r egeneration in ischemic acute renal failure (ARF) in rats. Unilateral ischemic injury was provoked by a 60-min left renal artery occlusion i n right-nephrectomized (Nx) and sham-nephrectomized (sham-Nx) rats. Un inephrectomy attenuated tubular damage 48 h following the renal ischem ia. Apoptotic cells were found in renal tissue as early as 3 h after r eperfusion and increased in number by 12 h. The ''ladder'' pattern of DNA fragments on agarose gel electrophoresis was also apparent in isch emic kidney. Uninephrectomy reduced apoptotic cells and DNA fragmentat ion. The expression of proliferating cell nuclear antigen (PCNA) could be seen 24 h after reperfusion and progressively increased thereafter . PCNA expression in ischemic kidney was greater in Nx than sham-Nx ra ts at 24 h after renal reperfusion. These data suggest that uninephrec tomy reduces apoptotic cells and DNA fragmentation and enhances PCNA e xpression. The reduced apoptotic cell death and enhanced cell regenera tion may be importantly involved in the uninephrectomy-induced attenua tion of ischemic acute renal failure in rats.