THE REPETITIVE ACTIVATION OF EXTRACELLULAR SIGNAL-REGULATED KINASE ISREQUIRED FOR RENAL REGENERATION IN RAT

In this study, we investigated the activation of p42 extracellular sig nal-regulated kinase (ERK2) during renal regeneration after HgCl2-indu ced acute renal failure (ARF) in rat. ERK2 activation was observed at 5 and 29 hr after HgCl2, injection, respectively. The tyrosine phospho rylation of hepatocyte growth factor receptor (c-MET) occurred between 2.5 and 5 hr after the treatment. On the other hand, the phosphorylat ion of epidermal growth factor receptor (EGFR) was transiently observe d at 29 hr after the injection. The peak of ornithine decarboxylase ac tivity as a marker of G(1) phase was at 10 hr, and subsequently the la beling index of proliferating cell nuclear antigen as a marker of S ph ase increased at 53 hr. These results indicate that the repetitive act ivation of ERK2 related to the phosphorylation of c-MET and EGFR is re quired for the renal regeneration in HgCl2-induced ARF of rat.