title: Nuclear condensation and fragmentation following cerebral hypoxia-ischemia occurs more frequently in immature than older rats.
abstract: Apoptotic cell death is associated with condensation and fragmentation of the nuclear chromatin into apoptotic bodies. Such nuclei occur frequently following cerebral hypoxia-ischemia in 1 week old rats but seem sparse in older animals. We investigated the age dependence by counting pyknotic or punctate chromatin containing cells in the cerebral cortex of 1,2 and 4 week old animals subjected to cerebral hypoxia-ischemia. In 1 week old animals the majority of injured neurons in the cortex had nuclei with punctate condensed chromatin but few were pyknotic. In the 2 and 4 week old animals the majority of injured cells were pyknotic (P < 0.002). Electron microscopic studies demonstrated the presence of apoptotic bodies. The results suggest that immature brain retains a part of the developmental cell death "program' that is activated following hypoxia-ischemia.
authors.affiliation: Biosystems, Institute for Biodiagnostics, National Research Council Canada, Winnipeg, Canada.
authors.forename: R S
authors.initials: RS
authors.lastname: Sidhu
authors.forename: U I
authors.initials: UI
authors.lastname: Tuor
authors.forename: M R
authors.initials: MR
authors.lastname: Del Bigio
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D017209:Apoptosis; D001927:Brain Diseases / Q000473:pathology*; D002545:Brain Ischemia / Q000473:pathology*; D002467:Cell Nucleus / Q000648:ultrastructure*; D002540:Cerebral Cortex / Q000473:pathology; D002843:Chromatin / Q000648:ultrastructure*; D000860:Hypoxia / Q000473:pathology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D002843:Chromatin