Increased p53 mRNA expression in liver and kidney apoptosis

The role of p53 in apoptosis is unclear; it is essential for the apoptotic response to certain stimuli, such as ionising radiation, but it is not required for others, such as castration-induced prostatic atrophy. Various tumour cell lines that are without functioning p53 are enabled to undergo apoptosis by transfecting wild type 53. The regulation of p53 mRNA is determined here, in two in vivo models of apoptosis. The first is partial liver ischaemic atrophy due to distal portal vein ligation, and the second is unilateral hydronephrosis from ureteric ligation. Mild ischaemia and elevated pressure, respectively, are thought to both cause mild cellular damage, induction of p53 and cell death by apoptosis. In both models of apoptosis, upregulation of p53 is shown.