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目的：通过观察高压氧（ hyperbaric oxygen ， HBO ）对急性脊髓损伤（ spinal cord injury ， SCI）大鼠的受损脊髓组织血管内皮生长因子（ vascular endothelial growth factor ， VEGF）及缝隙连接蛋白（connexin43， CX43）表达的影响，探讨HBO促进脊髓损伤神经功能恢复的作用机制。方法健康成年SD大鼠160只，按数字表法随机分为4组，每组40只。 SCI组：采用改良Allen＇s方法，使用MASCIS脊髓损伤专用撞击器建立 SCI 模型；SCI ＋HBO 组：SCI 造模后辅助以 HBO 处理；假手术对照组（ sham surgery， SH组）：仅行椎板切除术，不造成SCI；SH＋HBO组：椎板切除术后辅助以HBO处理。每组再随机均分为1、3、7和14 d 4个亚组，每亚组10只。损伤后不同时间点，采用运动功能评分（ Basso， Beattie and Bresnassian locomotors rating scale ，BBB）评价后肢运动功能；手术取出受损节段脊髓组织，采用免疫组化法检测VEGF及CX43的表达。结果术后各时间点， SCI组和SCI＋HBO组BBB评分明显低于SH组和SH＋HBO组（P＜0．01）；术后7 d和14 d，SCI ＋HBO组BBB 评分（7 d：4．67±1．97，14 d：10．83±2．23）明显高于SCI组（7 d：1．83±0．75，14 d：6．67±2．16），差异有统计学意义（P＜0．05）。相对于SH组和SH＋HBO组，SCI组和SCI＋HBO组在各时间点脊髓组织中VEGF和CX43表达明显增加（P＜0．01）。 SCI＋HBO组在3、7、14 d脊髓组织中VEGF表达（3 d：81．16±10．37，7 d：96．00±8．50，14 d：84．67±8．39）较SCI组（3 d：71．68±8．45，7 d：81．92±9．63，14 d：73．30±7．96）显著增加，差异有统计学意义（P＜0．05）；SCI＋HBO组在3、7 d脊髓组织中CX43表达（3 d：72．46±7．52，7 d：67．10±8．06）较SCI组（3 d：83．65±8．70，7 d：77．64±7．78）显著减少，差异有统计学意义（P＜0．05），而术后14 d，SCI＋HBO组脊髓组织中CX43表达（74．81±10．05）明显高于SCI组（66．74±8．30）（P＜0．05）。结论 HBO通过改变受损脊髓组织中VEGF和CX43的表达水平而促进SCI后的神经功能恢复。 HBO治疗可明显促进SCI大鼠后肢运动功能的恢复。“,”Objective To explore the mechanism of hyperbaric oxygen ( HBO) in the enhancement of neurological function recovery in the rats following spinal cord injury , through the observation of the effects of HBO on the expressions of vascular endothelial growth factor (VEGF) and connexin 43 (CX43) in the injured spinal cord tissue .Methods One hundred and sixty healthy adult SD rats were randomly divided into 4 groups:the spinal cord injury group(or the SCI group), the SCI+HBO group, the sham surgery group (or thecontrol group) and the sham surgery +HBO group.In the SCI group, the spinal cord injury model was developed by using the modified Allen ’ s method and MASCIS spinal cord injury impactor .For the SCI+HBO group, the animals received HBO therapy following development of the SCI model .In the control group , the vertebral lamina in T10 was surgically opened , but without SCI .In the sham surgery +HBO group, the animals also received HBO therapy after laminotomy .The animals of the 4 groups were further subdivided at random into the 1d, 3d, 7d and 14d subgroups, each consisting of 10.The motor function of the hinder limb was evaluated by Basso Beattie Bresnahan ( BBB) scores at different time points after injury .The injured tissue of the spinal cord was collected and then , the expressions of VEGF and CX 43 were detected with immunohistochemistry . Results The BBB scores of the SCI and SCI +HBO groups at various time points after injury were significantly lower than those of the sham surgery group and the sham surgery +HBO group (P<0.01).Seven and 14 days after surgery, the BBB scores of the SCI +HBO group(7 d:4.67 ±1.97, 14 d:10.83 ±2.23) were significant higher than those of the SCI group (7 d:1.83 ±0.75, 14 d:6.67 ±2.16) (P<0.05).When compared with those of the sham surgery group and the sham surgery +HBO group , the expression levels of VEGF and CX 43 in the spinal cord for the SCI group and the SCI +HBO group were significantly increased at various time points (P<0.01).The expression of VEGF in the SCI +HBO group (3 d:81.16 ±10.37, 7 d:96.00 ±8.50, 14 d:84.67 ±8.39)was significantly higher than that of the SCI group (3 d:71.68 ±8.45, 7 d:81.92 ± 9.63, 14 d:73.30 ±7.96), and statistical significance could be noted , when comparisons were made between the 2 groups(P<0.05).The expression level of CX43 in the spinal cord of the SCI +HBO group (3 d:72.46 ±7.52, 7 d:67.10 ±8.06) was significantly lower than that of the SCI group (3 d:83.65 ±8.70, 7 d:77.64 ±7.78), and statistical significance could be seen , when comparisons were made between them (P<0.05).However, the expression level of CX43 at d 14 after surgery in the spinal cord of the SCI +HBO group (74.81 ±10.05 ) was significantly higher than that of the SCI group ( 66.74 ±8.30 ) ( P <0.05 ). Conclusions HBO could obviously improve the neurological recovery of the hinder limb of the SCI rat , through enhancing the expression levels of VEGF and CX 43 following injury of the spinal cord.