高压氧对大鼠急性脊髓损伤炎症因子表达的影响

Objective To investigate the effects of early HBO therapy on the expressions of pro inflammatory cytokine mRNA including tumor necrosis factor-α (TNF-α ) and interleukin-10 (IL-10) following spinal cord injury (SCI) in rats. Methods Forty SD rats were randomly divided into 3 groups:the sham operation group (n=4) , the SCI group (n = 18) , and the hyperbaric oxygen group (n = 18). Spinal cord injury model was developed by using the modified Allen impact. Then, the SCI group and the HBO group received HBO therapy 2 hours after injury, once a day. And 3 rats were randomly selected at 6, 12, 24, 72, 120 and 168 h following injury to take samples of injured spinal cord tissue and measure dynamic changes in the expressions of TNF-α, IL-10 mRNA by semi-quantitative RT-PCR method. Results Faint expression of the cytokine mRNA could be noticed in the sham group. The expression of TNF-α mRNA in the injured spinal cord tissue in the SCI group elevated gradually, increased obviously at 12 h after injury and reached peak at 24 h, and its high expression maintained till 72 h after injury. The tendency in the expression of TNF-α mRNA in the HBO group was identical to that of the SCI group, however, the amplitude in the increase of TNF-α mRNA decreased (P＜0. 05). The expression of IL-10 mRNA in the SCI group began to increase at 12 h after injury and increased gradually over time and reached peak at 168 h. The expressions of both TNF-α and IL-10 mRNA were more consistent in the HBO group, with more obvious increase in the expressions of IL-10 mRNA. Conclusions HBO could reduce the release of pro-inflammatory cytokines and increase the expression of anti-inflammatory cytokines,resulting in reduction of secondary spinal cord injury,protection of the damaged nerve cells and promotion of recovery.     

不同压力高压氧治疗对大鼠脊髓损伤后细胞凋亡的影响

目的 观察不同压力的高压氧(HBO)对大鼠脊髓损伤(spinal cord injury,SCI)后细胞凋亡的影响,探讨HBO治疗SCI的最佳压力.方法 90只SD大鼠采用Allen's打击法造成SCI后随机分为5组:对照组(A组)、0.15 MPa HBO组(B组)、0.20 MPa HBO组(C组)、0.22 MPa HBO组(D组)和0.25 MPa HBO组(E组).损伤后第3、7、14天分别对5组大鼠进行取材,采用Tunel法检测凋亡细胞,光镜下观察,并对结果进行统计学分析;神经功能评价采用开放场地实验评估大鼠后腿运动功能(BBB评分).结果 与A组比较,HBO各压力组在3个时间点凋亡的细胞数有所减少,神经功能有所改善,且差异有统计学意义(P＜0.05).与B组比较,C、D和E组凋亡的细胞数有所减少,BBB评分改善,且差异有统计学意义(P＜0.05).与C组比较,E组于第3和第7天的差异有统计学意义(P＜0.05);第14天的差异无统计学意义(P＞O.05).结论 HBO能抑制SCI后细胞的凋亡,其作用在一定范围内与压力的升高相关.

Abstract：

Objective To study the effects of HBO at different pressures on apoptosis following spinal cord injury in rats and also to investigate ideal pressure value of hyperbaric oxygen(HBO) on spinal cord injury (SCI). Methods The SCI model was established with Allen's weight dropping by using 90 SD rats. Then, the animals were randomly divided into 5 groups following SCI: the control group ( group A); the HBO treatment group at 0. 15 Mpa (group B); the HBO treatment group at 0. 20MPa (group C); the HBO treatment group at 0. 22 Mpa ( group D); the HBO treatment group at 0.25 Mpa ( group E). Segments of injured spinal cord were collected from the animals of the 5 groups for studies on the 3rd, 7th, and 14th days after injury. The apoptosis cells were labeled with Tunel and the neurologic function of the spinal cord was assessed in the open field ( the BBB score ). Results The number of Tunel - positive cells decreased considerably and the BBB score improved significantly in all the animals of the HBO groups when compared with those of group A ( P ＜ 0. 05 ). Same results were found when the group C, group D and group E were compared with group B, with statistical significance( P ＜0. 05). The number of Tunel-positive cells were decreased considerably and the BBB score improved significantly on 3rd and 7th days in group E, when compared with those of group C( P ＜ 0. 05 ), with statistical significance( P ＜ 0. 05 ). However, no statistical significance could be noted on the 14th day (P ＜0.05). Conclusions HBO could inhibit apoptosis in rats following spinal cord injury, which might be correlated with the increase of pressure within a certain range.     

Effects of hyperbaric oxygen on TF、TNF-α in the rabbit model of steroid-induced avascular osteonecrosis of femoral head

Objective To investigate dynamic changes in serum TF and TNF-α in the rabbit model of steroid-induced avascular osteonecrosis of femoral head ( SANFH) and also to explore the mechanism of SANFH, as well as effects of hyperbaric oxygen ( HBO) on SANFH. Methods Seventy-eight New Zealand male rabbits were randomly divided into 3 groups:the normal control (group N) (7 animals), the model group (group M) (41 animals) and the HBO group (group H) (30 animals). The model group was subdivided into the immediate model group (the M0 group) (10 animals), the two-week model group (the M2 group) (10 animals), the four-week model group (the M4 group) (10 animals) and the six-week model group (the M6 group) (11 animals). The HBO group was further divided into the 2-week HBO therapy group (HBO2) (7 animals), the 4-week HBO therapy group (HBO4) (11 animals) and the 6-week HBO therapy group (HBO6) (12 animals). Through injection of endotoxin and methyl-prednisolone, rabbits in the group HBO2, HBO4 and HBO6 received HBO therapy 1 hour daily from the second day of the experiment. The durations of HBO therapy were 2 weeks ( HBO2), and 4 weeks respectively. The animals were sacrificed after blood samples were taken at respective blood collection time. Then, levels of TF, TNF-α in the serum were measured and the histological changes in the femoral heads were observed. Results Levels of TF and TNF-α in group M0 increased significantly, when compared with those of group N (P ＜0. 05 or P ＜0.01), while for the HBO subgroups the expression of TF and TNF-α measured at the same time points all decreased, when compared with that of the model subgroups (P＜0. 05 or P ＜0.01). To elaborate, TF levels in group M2 and M4 were much higher than those in group HBO2 and HBO4 ( P＜0. 01 ). TF level in group M6 was higher than that in group HB06 ( P ＜ 0.05). TNF-α in group M0 also increased significantly, when compared with that in group N( P ＜0.01). TNF-α levels in group M2 and M6 were also much higher than those in group HBO2 and HBO6 ( both P ＜0. 01 ). TNF-α in group M4 was higher than that in group HBO4 (P＜0.01). Histological examination revealed that tissues of the femoral heads in group N were normal, osteonecrosis and thrombus could be noted in group M2 and M4, hyperplasia fibrosis could be found in group M6, and osteonecrosis in HBO2 and HB04 groups seemed less severer than that in M2 and M4 groups, no thrombi in HBO2, HBO4 groups were noted, and growth of new bones were detected in HBO4 and HBO6. Conclusions The levels of TF and TNF-α levels increased in the rabbit model of SANFH, inducing blood coagulation. Thrombosis at the femoral heads was one of the causes of SANFH. HBO therapy could inhibit the release of TF and TNF-α, thus improving the abnormality of blood coagulation and enhancing treatment of osteonecrosis.     

K506促进神经干细胞移植后损伤脊髓神经传导通路的修复

目的 观察他克莫司(FK506)促进神经干细胞(neural stem cels,NSCs)移植后损伤脊髓神经传导通路修复的作用.方法 显微镜下动脉瘤夹压迫SD大鼠T8脊髓,建立压迫型脊髓损伤动物模型.损伤后7 d按随机数字表法分为三组:对照组,于损伤中心定向注射等渗盐水;细胞移植组,于损伤中心定向注射NSCs;FK506组,于损伤中心定向注射NSCs,同时按1 mg·kg-1·d-1连续7 d腹腔注射FKS06.连续观察1,2,4,8周,通过BBB评分、BDA顺行示踪、体感诱发电位(SEP)与运动诱发电位(MEP)监测,比较观察大鼠脊髓神经传导功能的恢复情况.结果 伤后后肢运动功能均有不同程度的恢复,4周时恢复速度最明显,8周时BBB最高评分可达6分;BDA顺行示踪,FK506组和细胞移植组在1周后有部分神经纤维通过,8周时各组均有部分BDA阳性标记的皮质脊髓束再生通过脊髓损伤部位,特别是FK506组可延续至距损伤中心1.7 cm.诱发电位结果显示,FKS06组在2周时SEP的潜伏期即明显缩短(P<0.05).4周后,FK506组MEP潜伏期与各组比较明显缩短(P<0.05),表明应用免疫抑制剂能促进NSCs对损伤脊髓的恢复,缩短SEP和MEP的潜伏期,早期对SEP改善明显,后期对MEP改善明显.结论 脊髓损伤大鼠移植NSCs后,系统应用FK506后具有神经保护和神经营养作用,可加快神经传导功能的恢复.

Abstract：

Objective To observe the effect of tacrolimus(FK506)in promoting repair of the injured spinal cord pathway after neural stem cell transplantation in rats. Methods A neurysm clip was used to compress the T8 spinal cord segment of SD rats under microscope to establish model of spinal cord injury.The rats were randomly divided into three groups seven days after injury,ie,control group (injection of normal saline at the injury center),transplantation group(injection of neural stem cells,NSCs,at the injury center),FK506 group(injection of NSCs at the injury center plus 7 days of intrapernerve conduction was compared by using the Basso-Beatfle-Bresnahan (BBB) scale,BDA tracing,somatosensory evoked potential(SEP)and motor evoked potentials(MEP)monitoring at 1,2,4 and 8weeks. Results The motor function of the hind limb after injury was recovered in various degrees with time,with the most significant recovery at 4 weeks.The BBB score reached 6,the maximum at 8 weeks.BDA tracing showed that some nerve fibers were found crossing the injured center of the spinal cord one week later in FK506 group and cell transplantation group,that BDA-positive labeled corticospinal tract fibets were seen across the injury site in all groups by the end ofthe eight weeks.In the FKS06 group,the regeneration could be observed even as 1.7 cm away from tlle injury center.SEP latency was significantly shorter in the FK506 group after two weeks(P<0.05)and the MEP latency in the FK506 group was shortened significantly at four weeks compared with the other groups(P<0.05),indicating that the immunosuppressants could promote the recovery of the injured spihal cord,shorten the latency of SEP and MEP,improve SEP at early stage and MEP at late stage．Conclusions Systemic application immuno suppressive agents FK506 plays an important role in neuroprotection and neurotrophy,which promotes the repair of the injured spinal cord after neural stem cell transplantation．     

少突胶质前体细胞移植治疗对大鼠脊髓损伤轴突髓鞘化的影响

Objective To investigate the effects of transplantation of oligodendrocyte precursor cells (OPCs) on axonal myelination after spinal cord injury in a rat model. Methods A rat model of spinal cord injury at the tenth thoracic vertebral level (T10) was produced by Allen weight-drop impact method. OPCs implantation was performed at the subacute stage of spinal cord injury. Effects of OPCs transplantation on axonal myelination after spinal cord injury were evaluated by HE staining, immunohistochemistry, myelin staining and transmission electron microscopy. Results The implanted cells were still observed in lesioned segments of spinal cord eight weeks after transplantation. The results of HE staining clearly showed better structure of spinal cord in OPCs-transplanted group than that of control group.Myelin staining also demonstrated that the amount of myelin in white matter of lesioned cord in the OPCs-transplanted group (7 802.42 ± 1085.58) was higher than that of the control group (5 055.98 ± 916.74)(P ＜0.01 ). Expression of myelin basic protein (MBP) was significantly increased in the OPCs-trans-planted group (8 544.44 ±812.78) as compared with that of the control group (5 243.83 ±808.27)(P＜0.01). Moreover, transmission electron microscopy further confirmed the improvement of micro-structure of myelination in OPCs-treated rats. Conclusion OPCs transplantation can improve axonal myelination in rat with spinal cord injury.     

皮层体感诱发电位监测轻度医源性脊髓冲击损伤的实验研究

目的 研究皮层体感诱发电位(somatosensory evoked potentials,SEP)在大鼠脊髓轻度冲击伤中的变化,评价其在预防此类医源性脊髓损伤中的临床价值.方法 SD大鼠24只,体重(340±28)g,按随机数字表法分为损伤组和对照组,每组12只.损伤组用改良重物坠击法制成C6节段脊髓轻度冲击伤模型,对照组仅行C6节段硬脊膜显露不做冲击.两组实验过程中均实施SEP监测,分别对两组和造模前后的SEP波形、幅值和潜伏期观察比较,并进行病理学研究.结果 对照组SEP波形、幅值和潜伏期未出现显著变化;损伤组SEP在脊髓冲击性损伤后波形和幅值发生显著变化,由损伤前的(1.3±0.7)μV降为(0.5±0.4)μV(P<0.05),而潜伏期差异无统计学意义[损伤前(11.1±2.1)ms:损伤后(10.7±1.3)ms(P>0.05)].该异常变化仅短暂出现在损伤后(5.7±3.2)min,持续(7.1±3.3)min.组织学观察发现,损伤后脊髓内散在灶状出血,而对照组未见组织学异常.结论 脊髓轻度冲击伤可引起SEP短暂异常,术者应密切注意术中SEP变化.术中SEP突然异常可能与手术操作中冲击和震荡所致脊髓损伤有关,应该考虑及时使用预防性脊髓保护措施.

Abstract：

Objective To investigate the changes of somatosensory-evoked potential(SEP)during an mild impact spinal cord injury in rats 80 as to evaluate its potential value in prevention of such iatrogenic damage. Methods Twenty-four SD rats weighing(340±28)g were randomly divided into two groups,ie,sham control group(only exposure without impact at C6)and injury group(mild impact spihal cord injury at C6).SEP wss recorded in both groups.The changes of SEP in waveform,amplitude and latency were observed and compared between groups and between operations.The gross dissection and histologic analysis were performed after surgery for comparative study. Results SEP waveforms,amplitude and latency showed no significant change in the sham control group.In contrast,the SEP waveform and amplitude animals showed significant changes in the injury group after impact spinal cord injury and the amplitude was decreased from pre-injury(1.3±0.7)μV to post-injury(0.5±0.4)μV(P<0.05),while the latency showed no significant difference between(11.1±2.1)ms pre-injury and(10.7±1.3)ms post-injury(P>0.05).However,this abnormal change appeared in a temporary period at(5.7±3.2)minutes after impact and lasted for about(7.1±3.3)minutes.Diffused hemorrhagic nidus could be seen in the injured cord,which was not found in the sham control group. Condusions Mild impact spinal cord injury may induce transient abnormalities of SEP in waveform and amplitude,which requires careful monitoring in clinical practice.The sudden change in SEP may be associated with impact and vibration damage to the spinal cord,suggesting timely use of protection measures for spinal cord.     

高压氧对激素性股骨头坏死兔血中TF、TNF-α的影响

目的 通过研究激素性股骨头坏死(steroid-induced avascular necrosis of the femoral head,SANFH)兔血组织因子(TF)和肿瘤坏死因子(TNF-α)的动态变化及高压氧(hyperbaric oxygen,HBO)对其影响,探讨SANFH发生机制和高压氧治疗的作用机制.方法 健康新西兰白兔78只,按数字随机表法分为3组:正常对照组(N组)7只,模型组(M组)41只,高压氧组(HBO组)30只.模型组又分为造模即刻组(M0组)10只,造模2周组(M2组)10只、造模4周组(M4组)10只、造模6周组(M6组)11只.HBO组分为:2周HBO组(HBO2组)7只、4周HBO组(HBO4组)11只、6周HBO组(HBO6组)12只.采用注射内毒素加甲强龙的方法对模型组及HBO组进行造模处理,HBO组在制模后开始HBO处理,每天1次,并于制模2周、4周、6周分别取静脉血检测TF、TNF-α的变化,于相应取血时间点取血后处死实验动物,取双侧股骨头组织进行组织学观察.结果 M各组TF[M0:(281.42±46.71)pg/ml,M2:(242.25±131.87)pg/ml,M4:(176.39±66.39)pg/ml,M6:(121.32±107.70)pg/ml]、TNF-α[M0:(418.83±75.99)pg/ml,M2:(424.41±57.01)pg/ml,M4:(424.05±136.44)pg/ml,M6:(344.34±112.89)pg/ml]均高于N组[TF:(137.55±21.65)pg/ml,TNF-α:(312.17±31.12)pg/ml],P＜0.05或P＜0.01;而HBO各组与M各组同时间点比较其表达均降低,P＜0.05或P＜0.01;组织学结果:N组股骨头组织形态正常,M组股骨十骺端髓腔内骨髓组织脂肪细胞增多增大、可见变性及片状坏死、炎性细胞浸润、出血、水肿及微小血管血栓、骨髓腔纤维化、造血细胞减少、股骨头萎缩明显;HBO各组脂肪变性、坏死出现率与M组比较明显减少,骨小梁间骨髓炎症反应明显减轻,未见到血栓形成,可见到骨母细胞活跃增生、骨髓纤维化、新生骨形成、股骨头萎缩不明显、骨基质正常.结论 兔SANFH时血中TF、TNF-α含量增高,诱导了体内凝血反应,使股骨头处血栓形成,HBO治疗可抑制实验动物体内TF、TNF-α的释放,从而改善凝血功能的异常,治疗股骨头坏死.

Abstract：

Objective To investigate dynamic changes in serum TF and TNF-α in the rabbit model of steroid-induced avascular osteonecrosis of femoral head ( SANFH) and also to explore the mechanism of SANFH, as well as effects of hyperbaric oxygen ( HBO) on SANFH. Methods Seventy-eight New Zealand male rabbits were randomly divided into 3 groups:the normal control (group N) (7 animals), the model group (group M) (41 animals) and the HBO group (group H) (30 animals). The model group was subdivided into the immediate model group (the M0 group) (10 animals), the two-week model group (the M2 group) (10 animals), the four-week model group (the M4 group) (10 animals) and the six-week model group (the M6 group) (11 animals). The HBO group was further divided into the 2-week HBO therapy group (HBO2) (7 animals), the 4-week HBO therapy group (HBO4) (11 animals) and the 6-week HBO therapy group (HBO6) (12 animals). Through injection of endotoxin and methyl-prednisolone, rabbits in the group HBO2, HBO4 and HBO6 received HBO therapy 1 hour daily from the second day of the experiment. The durations of HBO therapy were 2 weeks ( HBO2), and 4 weeks respectively. The animals were sacrificed after blood samples were taken at respective blood collection time. Then, levels of TF, TNF-α in the serum were measured and the histological changes in the femoral heads were observed. Results Levels of TF and TNF-α in group M0 increased significantly, when compared with those of group N (P ＜0. 05 or P ＜0.01), while for the HBO subgroups the expression of TF and TNF-α measured at the same time points all decreased, when compared with that of the model subgroups (P＜0. 05 or P ＜0.01). To elaborate, TF levels in group M2 and M4 were much higher than those in group HBO2 and HBO4 ( P＜0. 01 ). TF level in group M6 was higher than that in group HB06 ( P ＜ 0.05). TNF-α in group M0 also increased significantly, when compared with that in group N( P ＜0.01). TNF-α levels in group M2 and M6 were also much higher than those in group HBO2 and HBO6 ( both P ＜0. 01 ). TNF-α in group M4 was higher than that in group HBO4 (P＜0.01). Histological examination revealed that tissues of the femoral heads in group N were normal, osteonecrosis and thrombus could be noted in group M2 and M4, hyperplasia fibrosis could be found in group M6, and osteonecrosis in HBO2 and HB04 groups seemed less severer than that in M2 and M4 groups, no thrombi in HBO2, HBO4 groups were noted, and growth of new bones were detected in HBO4 and HBO6. Conclusions The levels of TF and TNF-α levels increased in the rabbit model of SANFH, inducing blood coagulation. Thrombosis at the femoral heads was one of the causes of SANFH. HBO therapy could inhibit the release of TF and TNF-α, thus improving the abnormality of blood coagulation and enhancing treatment of osteonecrosis.     

高压氧对大鼠脊髓损伤后炎症因子的影响

目的 观察高压氧对大鼠脊髓损伤后外周血中炎症细胞因子及其运动功能恢复的影响。方法采用改良Allen’s法制作大鼠脊髓损伤模型。75只SD大鼠,随机分为三组：假手术组（n=15）,对照组（n=30）和高压氧组（n=30）。分别于治疗后4h、12h、1d、3d及5d时间点,利用BBB评分法对大鼠进行运动功能评分,同时应用放射免疫检测技术测定各时间点大鼠外周血中TNF-α、IL-6、IL-8及IL-10的含量。结果对照组和高压氧组的各炎性细胞因子水平,较假手术组均有不同程度升高（P〈0．05）;高压氧组BBB评分较对照组升高（P＜0．05）;高压氧组外周血中上述炎性细胞因子在各时间点均较对照组降低（P＜0．01）。结论高压氧可抑制外周血中炎性细胞活性,降低各炎性细胞因子水平,促进损伤恢复,具有保护受损脊髓组织的作用。     

嗅鞘细胞联合甲基强的松龙对大鼠脊髓损伤区神经中丝表达的影响

目的 观察嗅鞘细胞(olfactory ensheating cells,OECs)移植联合甲基强的松龙(methyprednisolone,MP)对大鼠脊髓损伤区神经中丝(neurofilament,NF)mRNA及蛋白表达的影响,探讨OECs移植联合应用MP促进损伤脊髓修复的机制.方法 以NYU脊髓打击法建立大鼠急...     

NF-κB在大鼠颅脑损伤后表达水平与细胞凋亡的关系

目的 探讨颅脑损伤后不同阶段NF-κB及其下游炎症因子与神经元凋亡的共变关系及可能的机制. 方法采用随机数字表法将大鼠分为颅脑损伤组、颅脑损伤+吡咯烷二硫代氨基甲酸盐(PDTC)组和假手术对照组,并在处理后6,24,168 h分别用免疫组化、RT-PCR、TUNEL法测定脑组织NF-κB、TNF-α和神经元凋亡水平. 结果在颅脑损伤后急性、亚急性期,颅脑损伤组损伤灶周围脑组织中NF-κB、TNF-α较假手术对照组和PDTC组表达明显增高,与神经元凋亡指数呈正相关;在颅脑损伤晚期颅脑拟伤组损伤灶周围脑组织中NF-κB、TNF-α表达有所下降,但仍高于假手术对照组和PDTC组,与神经元凋亡指数呈负相关. 结论 NF-κB和下游炎症因子可能在颅脑损伤后急性、亚急性期有促进神经元凋亡作用,在慢性期有抑制神经元凋亡作用.     

高压氧治疗脊髓损伤后脊髓组织中增殖细胞核抗原的表达变化

为探讨高压氧(HBO)对脊髓损伤(SCI)大鼠脊髓组织中增殖细胞核抗原(PCNA)表达的影响，笔者观察了HBO治疗后脊髓的组织学改变及PCNA的表达变化。结果显示，损伤后，脊髓组织出血、水肿、空泡变性、神经纤维排列紊乱、断裂；PCNA强阳性表达于神经元细胞中。治疗组中，0．1MPa HBO组的HE及免疫组织化学染色结果与损伤组相似；而0．25MPa HBO组则组织水肿消失，出血、空泡变性减轻，神经细胞形态恢复，结构排列相对完整；PCNA的表达强度较损伤组下降。说明PCNA能明确提示细胞的增殖指数；HBO治疗可阻止或减轻脊髓损伤的病理变化，有效修复脊髓组织的结构和功能。     

高压氧对实验性减压病兔脊髓bFGF表达的影响

目的探讨实验性减压病兔脊髓bFGF的改变及高压氧对其影响。方法实验家兔随机分为7组：正常组、减压病3h组、减压病3d组、高压氧3h组、高压氧3d组、常氧高压氮3h组、常氧高压氮3d组。采用快速减压方法制备减压病模型，用免疫组织化学方法检测胸髓及腰髓中bFGF表达。结果（1）快速减压后各组bFGF表达均较正常组增加（P〈0．01），3h组之间无差异（P〉0．05）；（2）减压病3d组较3h组bFGF表达显著增高（P〈0．01），高压氧3d组较3h组显著降低（P〈0．01），常氧高压氮3d组较3h组有所降低（P〈0．05）；（3）高压氧3d组与常氧高压氮3d组均较减压病3d组显著降低（P〈0．01），高压氧3d组较常氧高压氮3d组降低（P〈0．05）。结论减压病脊髓损伤后bFGF表达增加；高压氧和常氧高压氮对减压病脊髓损伤起保护作用，高压氧效果优于常氧高压氮。     

TNF-α、Caspase-3在大鼠脊髓损伤后神经细胞凋亡中相关性研究

目的探讨大鼠脊髓损伤后肿瘤坏死因子-α(TNF-α)、天冬氨酸特异性半胱氨酸蛋白酶-3(Caspase-3)在神经细胞凋亡中的动态表达,验证TNF-α和Caspase-3之间的相关性。方法将70只成年健康SD大鼠按Nystrom法建立大鼠脊髓(T8、T9)急性压迫损伤模型,HE染色观察脊髓组织病理学变化;免疫组化染色测定各时间点TNF-α、Caspase-3的表达变化;原位末端脱氧核糖核酸转移酶介导的脱氧尿苷三磷酸(d UTP)标记法(TUNEL法)检测神经细胞的凋亡水平;通过Western blot法检测大鼠脊髓中TNF-α、Caspase-3蛋白的表达水平。结果正常大鼠脊髓神经细胞TNF-α、Caspase-3的阳性细胞表达率较少;脊髓损伤后8 h,脊髓神经细胞中TNF-α、Caspase-3的阳性表达率明显增多,分别为(24.13%±3.02%)及(40.79%±3.43%),1 d达高峰,分别为(51.36%±4.26%)及(70.78%±5.97%),3 d表达减弱,分别为(20.24%±2.93%)及(37.71%±2.88%),与正常大鼠比较,差异有统计学意义(P<0.01)。TUNEL阳性细胞率在大鼠脊髓损伤后8 h明显增多(39.81%±2.27%),1 d达高峰(71.58%±3.87%),3 d表达减弱(40.55%±2.36%),与正常大鼠比较,差异均有统计学意义(P<0.01)。大鼠脊髓损伤后1 d,与损伤组比较,抑制剂组TNF-α、Caspase-3、TUNEL阳性细胞率明显减少,差异有统计学意义(P<0.01)。造模后7 d,与空白对照组比较,损伤组TNF-α、Caspase-3蛋白的表达上升;与损伤组比较,抑制剂组TNF-α、Caspase-3蛋白的表达下降,差异有统计学意义(P<0.05)。结论脊髓损伤后TNF-α、Caspase-3的表达增强,TNF-α抑制剂使Caspase-3表达减弱,且其参与了脊髓损伤细胞凋亡的调节。     

高压氧对化疗相关外周神经痛的预防作用及其机制

目的探讨高压氧可否预防化疗相关外周神经痛(CIPNP),同时,以脊髓大麻素受体(CBRs)为主要靶点,探讨其作用机制。方法 75只雄性SD大鼠按随机数字表法分为5组,即空白对照组、模型对照组、高压氧干预组、高压氧+AM630组及高压氧+AM251组,每组15只。CIPNP模型采取紫杉醇腹腔注射法建立,所有干预组从第1次紫杉醇注射开始,隔日应用高压氧干预,共5次。高压氧+AM630组和高压氧+AM251组于每次高压氧干预前分别给予大麻素Ⅱ型受体(CBR2)阻滞剂AM630和大麻素Ⅰ型受体(CBR1)阻滞剂AM251腹腔注射。行为学测试使用von fery纤维毛分别于实验开始前及实验期间每隔7 d测试大鼠机械缩足阈值(MWT);应用Western blotting检测脊髓CBR1、CBR2的表达;应用免疫组化及Western blotting检测脊髓星形胶质细胞标志物胶质纤维酸性蛋白(GFAP)的表达;应用酶联免疫吸附法(ELISA)检测脊髓炎性细胞因子白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)的表达。结果与空白对照组相比,模型对照组MWT明显降低,差异有统计学意义(P<0.01),实验第21天差异最明显[(15.46±2.83)gvs.( 4.33±3.53)g],差异有统计学意义(P<0.01);脊髓GFAP、IL-1β、TNF-α表达均明显升高,差异有统计学意义(P<0.05或P<0.01)。与模型对照组相比,高压氧干预组MWT及脊髓CBR2均明显升高,差异有统计学意义(P<0.05);脊髓GFAP、IL-1β、TNF-α表达均明显降低,差异有统计学意义(P<0.05);腹腔注射AM630可逆转上述作用,而腹腔注射AM251无类似作用。结论高压氧可以预防紫杉醇诱导的CIPNP,其机制可能与高压氧激活脊髓CBR2,并进一步阻断脊髓胶质细胞活化及炎性细胞因子表达有关。     

核因子-κB在大鼠肺型氧中毒发病中的作用

目的 探讨核因子(NF)-κB在大鼠肺型氧中毒发病中的作用.方法 32只SD大鼠随机分为正常对照组及230 kPa高压氧暴露2、6、10 h组.观察肺组织病理变化以及NF-κB和肿瘤坏死因子a(TNF-α)在肺组织中含量的变化.结果 (1)病理检查发现肺组织在高压氧暴露6 h组出现炎症改变,10 h组肺损伤加重.(2)肺组织细胞核中NF-κB P65含量在高压氧暴露2 h组中明显增高,6 h组中达高峰,10 h组中下降但仍高于正常对照组.(3)肺组织TNF-α mRNA表达及肺匀浆中TNF-α浓度在高压氧暴露6 h组中明显增高,10 h组中继续增高.结论 高压氧可以通过活化NF-κB诱导TNF-α高表达从而介导氧中毒的肺损伤.