Acute renal failure continues to have an unacceptably high mortality rate. Ischemic renal injury is the most common cause of acute renal failure. Understanding the molecular mechanisms of cell death and regeneration is important for designing future therapeutic strategies. Recent interest in our laboratory has focused on molecular response after ischemic renal injury and, in particular, genes that are important in cell death and repair after ischemia. The identification of genes that are differentially expressed after ischemia has led to new information regarding the identity of possible mediators of cell death and regeneration in renal tubular epithelial cells.