[Effect of hyperbaric oxygen therapy administered at different time on white matter damage following hypoxic-ischemic brain damage in neonatal rats].
OBJECTIVE
A recent study has suggested that hyperbaric oxygen (HBO) therapy administered within 3 hrs following hypoxic-ischemic brain damage (HIBD) may alleviate brain white matter damage (WMD) in neonatal rats. However it is unclear whether a delayed HBO therapy (more than 3 hrs following HIBD) has neuroprotective effects in neonatal rats. This study aimed to explore the effect of HBO therapy administered at different time points following HIBD on WMD in neonatal rats.


METHODS
The HIBD model was prepared according to the Rice-Vannucci procedure in 7-day-old Sprague-Dawley rats. HBO therapy was administered at 3, 6, 12, 24 or 72 hrs after HIBD, once daily for consecutive 7 days. T-maze test, the foot-fault test and the radial arm maze test were performed after 14 days of HIBD. Myelin basic protein (MBP) in the callositas and corpora striata was examined by immunohistochemical method 28 days after HIBD.


RESULTS
The rats receiving HBO therapy at 3, 6 and 12 hrs after HIBD performed significantly better in the T-maze test, the radial arm maze test and the foot-fault test than the untreated HIBD rats. There were no significant differences in the behavioral test results between the HBO-treated groups administered HBO at 24 and 72 hrs after HIBD and the untreated HIBD group. The MBP expression in the HBO-treated groups treated within 12 hrs after HIBD was significantly higher than that in the untreated HIBD group (P < 0.05). When the HBO therapeutic window was delayed to 24 hrs after HIBD, there were no significant differences in the MBP expression between the HBO-treated and the untreated HIBD groups.


CONCLUSIONS
HBO therapy administered within 12 hrs following HIBD can alleviate brain WMD in neonatal rats, but the efficacy of HBO therapy administered 24 hrs after HIBD does not appear to be satisfactory.
Wang
Xiao-Li
XL
Department of Pediatrics, Xiangya Hospital, Central South University, Changsha 410008, China.
Yang
Yu-Jia
YJ
Wang
Qing-Hong
QH
Yu
Xiao-He
XH
Xie
Min
M
Liu
Chen-Tao
CT
Wang
Xia
X
D000818:Animals; D000831:Animals, Newborn; D001921:Brain / Q000473:pathology*; D005260:Female; D006931:Hyperbaric Oxygenation; D020925:Hypoxia-Ischemia, Brain / Q000378:metabolism / Q000473:pathology / Q000523:psychology / Q000628:therapy*; D007150:Immunohistochemistry; D008297:Male; D018782:Maze Learning; D004676:Myelin Basic Protein / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D004676:Myelin Basic Protein