Molecular events involved in neuronal death induced in the mouse hippocampus by in-vivo injection of kainic acid

Apoptosis results from the activation of a programmed cellular cascade invo lving several mechanisms. In the present study, we have investigated the im plication of three molecules of this cascade, p53, Bax and caspase-3, in ne uronal death induced by kainic acid (KA) administration in mouse hippocampu s. Using immunocytochemistry, western blot and quantification of enzyme act ivity, we observed in p53+/+ and p53-/- animals that KA induced neuronal de ath by both p53-dependent and independent pathways. Moreover, apoptosis (la beled by TUNEL) and the increase of bax and caspase-3 protein expression af ter the neurotoxic insult appeared to clearly depend on p53 expression. (C) 2001 Elsevier Science B V. All rights reserved.