Cell cycle induction in post-mitotic neurons proceeds in concert with the initial phase of programmed cell death in rat

Neuronal programmed cell death (PCD) is increasingly becoming recognized as a dynamic process that may be amenable to resolution. Critical to this res olution is the identification of the cellular pathways that modulate the in itial stages of apoptotic death. In this regard, we examined whether the ac tivation of a latent cell cycle was associated with the initial phase of PC D. We demonstrate that free radical nitric oxide induced PCD results in the rapid generation of membrane phosphaticlylserine residue exposure. This ea rly phase of PCD functions in parallel with an untoward attempt to enter th e cell cycle in the same population of post-mitotic neurons. We therefore o ffer an attractive molecular target to prevent or reverse neuronal PCD by e lucidating a novel mechanism through which the majority of neurons meet the ir demise by attempting to enter a latent cell cycle. (C) 2001 Published by Elsevier Science Ireland Ltd.