Hyperoxic exposure leads to cell death in the developing brain.
Premature infants have high incidence of motor and cognitive impairment in later life. Supraphysiological oxygen concentrations are routinely used in neonatal intensive care units and elicit injury to premature lungs and retina. Since the effects of hyperoxia on the developing brain are scarce, we studied the effects of high oxygen on this tissue. Wistar rat pups were exposed from birth until day 5 to 21% or 80% oxygen. The neuronal density and apoptosis in CA1 and dentate gyrus of hippocampus, prefrontal cortex, parietal cortex, subiculum, and retrosplenial cortex were assessed by immunohistochemistry and ELISA cell death assay. Neuronal density of the investigated brain areas were significantly decreased in the hyperoxia group. Furthermore, using ELISA cell death and TUNEL assays, we observed increased cell death in the developing brain. Our results show that hyperoxia induces cell death in the developing rat brain. This may be one of the important mechanisms that cause motor and cognitive impairment in later life of premature infants.
Yiş
Uluç
U
Department of Pediatric Neurology, School of Medicine, Dokuz Eylül University, Inciralti, 35340 Izmir, Turkey. ulyis@yahoo.com
Kurul
Semra Hiz
SH
Kumral
Abdullah
A
Cilaker
Serap
S
Tuğyan
Kazim
K
Genç
Sermin
S
Yilmaz
Osman
O
D000818:Animals; D000831:Animals, Newborn; D001921:Brain / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism / Q000473:pathology*; D016923:Cell Death / Q000502:physiology*; D004249:DNA Damage; D005260:Female; D006801:Humans; D018496:Hyperoxia; D020287:In Situ Nick-End Labeling; D007231:Infant, Newborn; D007234:Infant, Premature; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D009929:Organ Size; D010100:Oxygen / Q000009:adverse effects*; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar
D010100:Oxygen