1048
TYPE III
CELL DEATH IN NEONATAL RATS FOLLOWING CEREBRAL HYPOXIA-ISCHEMIA Zhou W1, Wu S-M2, Chen H-J2
1 Guangzhou Children’s
Hospital, Guangzhou, China 2 Shanghai Institute for
Pediatric Research, Shanghai, China Objective: To
investigate the forms of delayed neuronal death following cerebral
hypoxia-ischemia(HI) in neonatal rats. Methods: Using
HE staining and In situ end labeling (ISEL), the authors observed the
histological features of cells death in the cerebral cortex and hippocampus
at ipsilateral hemisphere in neonatal rat models of HI. Results: As
a special type of cell death, the type III cell death was observed in the
study during investigating cell death following HI in neonatal rat brains.
Under light microscope, the nuclear chromatin of type III cells condensed,
the cell volume shranked, showing characteristics of type I (apoptotic)
cells, in the meantime, those cells were rich in cytoplasm, and the
integrity of the plasma membrane was lost, showing characteristics of type
II (necrotic) cells. Type III cells had no perinuclear halo and apoptotic
bodies examined by ISEL. The evident increase of type I cells in the
ipsilateral hemisphere of group HI began at 6h following HI (21.3±3.5/10hpf),
peaked at 24h (63.7±3.2/10hpf),
which was higher than that of the control (7.3±2.3/10hpf),
p<0.001. There was no type III cells in the normal brain tissue, while
the type III cells were observed in the ipsilateral hemisphere at 24h
following HI (50.6±6.3/10hpf),and
the type III cells peaked at 48h (75.6±10.2/10hpf),
which was higher than the type I cells (42.3±4.5/10hpf)
at the same timepoint, p<0.01.Type III cells were mainly located in the
necrotic or perinecrotic areas. Conclusions:
Type III cell death was mainly involved in the delayed cell death following
hypoxic-ischemic injury except for the existence of necrosis and apoptosis.
Type III cell death was a special type of cell death, which related to
apoptosis and necrosis.