高压氧对新生大鼠缺氧缺血脑损伤后24h内脑细胞线粒体膜电势的影响

发布时间：2018-06-25 11:46

本文选题：新生鼠 + 缺氧缺血性脑损伤　；参考：《中南大学》2012年硕士论文

【摘要】：目的：围产期缺氧缺血(hypoxic-ischemic, HI)是导致新生儿脑细胞损伤的主要原因之一。高压氧(hyperbaric oxygen, HBO)是临床上治疗缺氧缺血性脑损伤(hypoxic-ischemic brain damage, HIBD)的方法之一,但其作用机制尚不完全明了。线粒体是所有细胞内制造能量的细胞器,线粒体膜电势(Mitochondiral Membrane Potential,△Ψm)是线粒体功能的标志,在HI损伤早期即发生变化。本研究的目的,是应用新生大鼠HIBD模型并模拟临床HBO治疗,通过观察HIBD损伤后24小时内脑皮质ΔΨm的变化,了解HBO对HIBD损伤后脑皮质细胞△Ψm的影响,探讨HBO是否是通过改善脑皮质细胞△Ψm和改善其线粒体功能而治疗HIBD。方法：将7日龄新生SD大鼠132只随机分为正常对照组,HIBD组及HIBD+HBO组(后两组按Rice法制作新生大鼠HIBD模型,大脑左侧为损伤侧),HBO+HIBD组动物在HI后立即给予HBO治疗,HBO结束的时间点记为0h点。动物按照处死时间点再分为0h,2h,4h,6h,12h,24h亚组(各组n=10)。各组动物断头处死后,制备脑皮质细胞悬液,给予ΔΨm标记物罗丹明123(Rodamine123, Rho123)孵育,用流式细胞仪检测Rho123的平均荧光强度(mean fluorescence level, MFL)、并以该MFL为△Ψm,分别记录各组左右侧大脑皮质ΔΨm绝对值和损伤侧/损伤对侧△Ψm比值。结果： 1.正常对照组：左侧Ψm为(4.72±0.12)MFL,左侧/右侧△Ψm比值为(1.20±0.05)。 2. HIBD组与正常组比较：HI后0h,2h,4h,6h,12h,24h各亚组左侧△Ψm均低于正常组,分别为(2.67±0.53)、(3.92±2.59)、(4.21±0.38)、(3.58±0.50)、(4.16±0.14)、(3.42±0.34)MFL,其中0h亚组与正常组比较差异具有统计学意义(P0.05)；HI后0h,2h,4h,6h,12h,24h各亚组左侧/右侧△Ψm比值均低于正常组,分别为(1.12±0.13)、(1.06±0.10)、(0.89±0.13)、(1.13±0.09)、(0.95±0.15)、(1.13±0.07),其中4h组与正常组比较差异具有统计学意义(P0.05)。HIBD后0h组、6h组、24h组与4h组比较差异具有统计学意义(P0.05)。 3. HIBD+HBO组与正常组比较：HIBD+HBO后0h,2h,4h,6h,12h,24h各亚组左侧△甲m分别为(2.58士1.06)、(4.03±1.77)、(4.53±0.43)、(4.68±1.76)、(3.85±0.06)、(3.09±0.48)MFL。其中0h、24h亚组与正常组比较,差异具有统计学意义(P0.05)。HIBD+HBO后4h、6h与O h差异具有统计学意义(P0.05)。左侧／右侧△甲m比值分别为(0.94±0.40)、(0.92±0.15)、(1.13±0.05)、(1.06±0.14)、(1.08±0.08)、(1.03±0.16)。其中0h、2h组左侧／右侧△Ψm比值与正常组比较,差异具有统计学意义(P0.05)。 4. HIBD组与HIBD+HBO组比较：HI后4h,6h,12h,24h时间点的左侧△Ψm值,两组之间差异具有统计学意义(P0.05),但各时间点的左侧／右侧△甲m比值,两组之间比较差异无统计学意义(P0.05)。结论： 1.HI可导致新生SD大鼠损伤侧脑皮质细胞△甲m以及损伤侧／损伤对侧△甲m比值的降低； 2.HI后立即给予单次HBO治疗可部分缓解HI后24h内损伤侧脑皮质细胞△Ψm的降低程度,但对损伤侧／损伤对侧△甲m比值的变化无明显影响； 3.HBO是否可通过改变损伤侧脑皮质细胞ΔΨm这一机制在短期内达到对HIBD的治疗作用,目前尚无法确定。
[Abstract]:Objective: perinatal hypoxic-ischemic (HI) is one of the main causes of neonatal brain cell damage. Hyperbaric oxygen (hyperbaric oxygen (HBO)) is one of the clinical methods for the treatment of hypoxic ischemic brain damage (hypoxic-ischemic brain damage, HIBD), but its mechanism is not completely clear. Mitochondria are all cells. Mitochondiral Membrane Potential (Membrane Potential) is a marker of mitochondrial function, which changes in the early stage of HI damage. The purpose of this study is to apply the HIBD model of neonatal rats and to simulate clinical HBO therapy. By observing the changes in the delta m within 24 hours after the injury of HIBD, we know HBO to HIBD loss. The effect of HBO on m after traumatic brain injury is to investigate whether HIBD. can treat HIBD. by improving the cortical cells' delta cell and improving its mitochondrial function.
Methods: 132 newborn SD rats of 7 days old were randomly divided into normal control group, HIBD group and HIBD+HBO group (the latter two groups were made up of HIBD model of neonatal rats by Rice, the left side of the brain as the injured side). The HBO+HIBD group was given HBO treatment immediately after HI, and the time point of the end of HBO was recorded as 0h points. The subgroup (group n=10). After the animals were killed, the cerebral cortex suspension was prepared, and the delta m marker was incubated with rhodamine 123 (Rodamine123, Rho123). The average fluorescence intensity of Rho123 (mean fluorescence level, MFL) was detected by flow cytometry, and the MFL was the m, the absolute value and loss of the left and right cortex of the cerebral cortex were recorded. The ratio of lateral Delta / injury to lateral delta m.
Result:
1. in the normal control group, the left m was (4.72 + 0.12) MFL, and the ratio of the left / right side was m (1.20 + 0.05).
2. HIBD group compared with the normal group: after HI, 0h, 2h, 4h, 6h, 12h, and 24h were lower than the normal group, respectively (2.67 + 0.53), (3.92 + 2.59), (4.21 + 0.38), (3.58 + 0.50), (4.16 + 0.14), (3.42 + 0.34) MFL, among which 0h subgroup was statistically significant (P0.05) The ratio of lateral delta m was lower than that of the normal group (1.12 + 0.13), (1.06 + 0.10), (0.89 + 0.13), (1.13 + 0.09), (0.95 + 0.15), (0.95 + 0.15), (1.13 + 0.07). The difference between group 4H and normal group was statistically significant (P0.05).HIBD after 0h group, 6h group, and 24h group had statistical significance compared with 4H group (P0.05).
3. HIBD+HBO group compared with the normal group: 0h, 2h, 2h, 4h, 6h, 12h, 24h, 12h, 24h, and 24h of each subgroup are (2.58 1.06), (4.03 + 1.77), (4.53 + 0.43), (4.68 + 1.76), (3.85 + 0.06), (3.09 + 0.48) MFL. 0h, and the difference has statistical significance compared with the normal group. (P0.05). The left / right delta M ratio was (0.94 + 0.40), (0.92 + 0.15), (1.13 + 0.05), (1.06 + 0.14), (1.08 + 0.08), (1.03 + 0.16), of which the ratio of m to the left / right m of group 2H was compared with the normal group (P0.05).
4. HIBD group compared with the HIBD+HBO group: 4h, 6h, 12h, 24h point left delta m value after HI, the difference between the two groups was statistically significant (P0.05), but there was no statistical difference between the two groups (P0.05).
Conclusion:
1.HI could induce the decrease of delta SD m and the ratio of injury side / injury side to m in injured brain cortex of neonatal rats.
A single HBO treatment immediately after 2.HI could partly alleviate the reduction of delta m in the injured side of the lateral cerebral cortex after HI, but had no significant effect on the change of the lateral delta M ratio of the injured side / injury.
Whether 3.HBO can achieve the therapeutic effect of HIBD in short term by changing the mechanism of delta m in injured side cortical cells is still uncertain.
【学位授予单位】：中南大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R722.1

【相似文献】