摘要目的 观察高压氧(HBO)治疗对大鼠大脑皮质损伤后胶质疤痕形成的影响,并初步探讨其对炎性反应产生抑制作用的内在作用机制.方法 选取健康成年雄性SD大鼠96只,建立大脑穿刺损伤模型,采用随机数字表法将其分为对照组和治疗组,每组48只,对照组不做特殊干预处理,治疗组则给予HBO治疗.分别于脑穿刺损伤后1、3、7、14和28 d取大鼠右侧大脑组织,利用免疫组化染色比较2组大鼠损伤灶周围星形胶质细胞和小胶质细胞的数目变化,并通过ELISA法测定脑组织内肿瘤坏死因子α(TNF-α)、白细胞介素1β(IL-1β)的含量.结果 制模后7、14和28 d,对照组大鼠的伤口面积分别为(2.73±0.05) μm2、(3.42±0.18)μm 2、(2.41±0.09) μm2,与制模后7d及14 d比较,制模后28 d时的伤口面积明显缩小(P＜0.05)；治疗组大鼠制模后7、14和28 d的伤口面积分别为(2.78 ±0.12)μm2、(2.59±0.08) μm2、(1.20±0.06) μm2,与制模后7d比较,制模后14 d时的伤口面积缩小(P＜0.05),且制模后28 d时的伤口面积进一步缩小(P＜0.05),制模后14 d及28 d时的伤口面积均小于对照组(P＜0.05).与制模后7d比较,对照组及治疗组制模后14 d和28 d的星形胶质细胞数目均增多(P＞0.05)；与组内制模后14 d比较,对照组及治疗组制模后28 d的星形胶质细胞数目下降(P＜0.05)；与对照组同时间点比较,治疗组星形胶质细胞的数目少于对照组(P＜0.05).与制模后1d比较,对照组及治疗组制模后3d、7d的小胶质细胞均增多(P＞0.05)；与组内制模后7d比较,对照组及治疗组制模后14 d的小胶质细胞数目下降(P＜0.05)；与对照组同时间点比较,治疗组小胶质细胞的数目少于对照组(P＜0.05).与制模后1d比较,对照组制模后3d及7d的TNF-α浓度均较高(P＞0.05),但制模后7d的TNF-α浓度较制模后3d低(P＜0.05)；制模后3d及7d,对照组IL-1β浓度和治疗组TNF-α浓度均呈先升高后降低趋势；治疗组IL-1β浓度则呈逐渐降低趋势(P＜0.05).与对照组同时间点比较,治疗组TNF-α浓度及IL-1β浓度均较低(P＜0.05).结论 HBO治疗可促进脑穿刺损伤伤口愈合,减少胶质疤痕形成,其机制可能与星形胶质细胞及小胶质细胞活化水平下调、参与炎性反应的细胞因子含量减少有关.

abstractsObjective To observe any influence of hyperbaric oxygen (HBO) treatment on the formation of glial scars,and to explore how HBO suppresses the inflammatory reaction to injury.Methods A total of 96 healthy,adult,male,Sprague-Dawley rats were used to model cerebral puncture injury.They were then randomized into a control group and a treatment group,with 48 rats in each group.The treatment group received HBO treatment,while the control group received no special treatment.At 1,3,7,14 and 28 days after the puncture injury,the rats' right brain tissues were harvested and immunohistochemical staining was employed to compare the changes in number of astrocytes and microglial cells around the injury in the two groups.The level of tumor necrosis factor α (TNF-α) and interleukin 1 β (IL-1β) in the cerebral tissue was examined using ELISA.Results Among the control group the average wound areas after 7,14 and 28 days were (2.73 ± 0.05)μm2,(3.42 ± 0.18)μm2 and (2.41 ± 0.09) μm2,a significant reduction after 28 days compared with 7 and 14 days.The corresponding average wound areas of rats in the treatment group were (2.78±0.12)μm2,(2.59 ±0.08)μm2 and (1.20 ±0.06)μm2.There the average wound area had decreased significantly after 14 days,and the further reduction after 28 days was also significant.The numbers of GFAP-positive astrocytes at 14 and 28 days had increased significantly compared with after 7 days in both the control group and the treatment group.The average number of GFAP-positive astrocytes in the control group at 28 days had decreased significantly compared with after 14 days.Compared with the control group at the same time points,the number of GFAP-positivc astrocytes in the treatment group was significantly less.After modeling,the number of ionized calcium-binding adapter molecule Ⅰ (Ibal)-positive microglial cells increased significantly,but there was a significant decrease in both the control and treatment groups by 7 days.The average number of Ibal-positive microglial cells in the treatment group was significantly less than in the control group at all of the time points.Compared with the first day after modeling,the TNF-α concentration of the controls at 3 and 7 days was significantly higher,but by the 7th day it was significantly lower than it had been after 3 days.The average IL-1β concentration in the control group and TNF-α concentration in the treatment group had increased by day 3,but then decreased by day 7.The IL-1β concentration of the treatment group declined gradually.The average TNF-α and IL-1 β concentrations of the treatment group were significantly lower than those of the control group at all of the time points.Conclusion HBO treatment has a relatively good curative effect on cerebral puncture injury.It can accelerate wound healing and reduce the formation of glial scars.Its mechanism could be related to the deactivation of astrocytes and microglia cells and reducing the levels of cell factors that promote inflammation.