目的：研究发现早期高压氧（HBO）治疗可以减轻缺氧缺血性脑损伤（HIBD）新生大鼠的脑白质损伤。但延迟开始治疗的时间是否也有同样的作用尚不清楚。该文探讨不同时间窗 HBO 治疗对 HIBD 新生大鼠脑白质损伤的影响，从而探讨 HBO 治疗 HIBD 的时间窗。方法：采用 Rice 法制成 HIBD 模型，分别于HIBD 后 3，6，12，24，72 h 开始给予 HBO 治疗，每日1次，连续 7 d。HIBD 后 14 天（生后21天）开始采用盲法进行T迷宫试验、放射性迷宫测试、足错误测试行为学测试；测试完毕，用髓鞘碱性蛋白 （MBP）免疫组化法检测胼胝体与纹状体区髓鞘蛋白。结果：HIBD 后 3，6，12 h HBO 治疗各组T 迷宫测试、放射性迷宫试验和足错误测试的测试结果均优于HIBD模型组（P<0.05）。HIBD 后24，72 h HBO 治疗组行为学测试结果与HIBD模型组比较，差异无显著性意义。HIBD 后 3，6，12 h HBO 治疗各组大脑皮层胼胝体与纹状体区域 MBP 吸光度显著高于 HIBD模型组，差异有显著性意义（P<0.05），而HIBD 后24，72 h HBO 治疗组与 HIBD模型组相比差异无显著性。结论：HIBD 后 12 h 内HBO 治疗可以显著改善脑白质损伤， HIBD 后 24 h 治疗则疗效不显著。［中国当代儿科杂志，2007，9（4）：308-312］

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.［Chin J Contemp Pediatr, 2007, 9 (4):308-312］