内皮素A受体在颅脑创伤的脑微血管内皮细胞上的表达及意义

了解内皮素Ａ受体在颅脑创伤后脑微血管内皮细胞中的作用。方法对家兔致克额顶为着力部位的撞击伤，动态研究脑组织呐皮素含量及内皮素Ａ受体ｍＲＮＡ表达和定位变化，内皮素Ａ受体拮抗剂ＢＱ１２３治疗效应，观察对脑创伤后局部脑血流量和脑不量的影响。     

前列腺素E2及其受体EP3A与创伤性脑水肿的关系

目的：研究前列腺素Ｅ２（ＰＧＥ２）及其受体ＥＰ３Ａ与创伤性脑水肿的关系．方法：运用形态学、放射免疫及分子生物学等方法，对模型脑外伤大鼠伤区及创伤对侧相应区域脑含水量、血脑屏障（ＢＢＢ）通透性、ＰＧＥ２含量、ＥＰ３ＡｍＲ－ＮＡ表达，以及消炎痛对其影响进行动态定量检测．结果：（１）伤后２小时，伤区脑组织ＰＧＥ２及含水量显著增高（Ｐ＜０．０５），ＢＢＢ严重破坏．这些变化于伤后２４小时达高峰，伤后４天均显著下降．消炎痛预处理动物可显著减轻上述变化．（２）伤后２小时，伤区脑组织ＥＰ３ＡｍＲＮＡ密度显著下降（Ｐ＜０．０５），伤后２４小时降到最低，伤后４天又开始回升．在创伤对侧或远离伤区，ＥＰ３ＡｍＲＮＡ密度则显著高于伤区，接近正常水平．应用消炎痛，在伤区病变好转的同时，也可见ＥＰ３ＡｍＲＮＡ密度的增加．结论：（１）ＰＧＥ２与脑含水量及血脑屏障通透性呈显著正相关，参与了创伤性脑水肿的发生发展．（２）伤后脑组织ＥＰ３ＡｍＲＮＡ表达似与脑组织伤后自我保护机制有关．（３）消炎痛可以减轻大鼠伤后脑组织的继发性损害．     

CEC,ET,ETAR与脑外伤后脑水肿,缺血性脑损害关系的实验研究

目的研究脑外伤后脑水肿、缺血性脑损害的发生与循环内皮细胞（CEC）、内皮素（ET）及内皮素A受体（ETAR）变化的关系。方法建立颅脑撞击伤的动物模型,于伤后不同时相测定CEC、血、CSF、不同脑区ET含量,原位杂交检测ETARmRNA表达,测定脑血流量、脑含水量,光镜、电镜观察神经病理学改变。结果脑外伤后CEC、ET含量显著升高,ETARmRNA表达增强,并与伤情轻重呈正相关。结论脑外伤后脑血管内皮细胞脱落致血脑屏障（BBB）破坏,升高的ET与ETAR结合使血管通透性增高,脑血流减少,参与了脑水肿、缺血性脑损害的发生。     

高压氧对大鼠颅脑创伤后脑损伤和脑水肿的影响

目的：探讨高压氧对大鼠颅脑创伤后脑损伤和脑水肿的影响。方法：将大鼠随机分为对照组、脑创伤组和高压氧（ＨＢＯ）组。采用ＢＩＭ－Ⅲ型撞击机撞击大鼠右侧颅顶，复制闭合性颅脑损伤，于伤后２４小时由心脏取血处死，测定脑组织含水率、伊文斯蓝（ＥＢ）含量及脑组织和血浆脂质过氧化物──丙二醛（ＭＤＡ）含量。结果：（１）脑外伤组大鼠右侧脑组织含水率、脑组织及血浆ＭＤＡ含量均显著高于对照组（Ｐ＜０．０１或Ｐ＜０．０５）；右侧脑组织含水率及ＭＤＡ含量显著高于对侧（Ｐ＜０．０１或Ｐ＜０．０５），右侧脑组织ＥＢ含量较对照组升高，但Ｐ＞０．０５；（２）ＨＢＯ组右侧脑组织含水率及脑组织ＭＤＡ含量显著低于脑外伤组（Ｐ＜０．０１或Ｐ＜０．０５），而与对照组及左侧无明显差别；血浆ＭＤＡ、脑ＥＢ含量与对照组、脑外伤组及左侧均无明显差别。结论：ＨＢＯ能减少脑外伤脑组织氧自由基的生成，减轻脑损伤和脑水肿。     

兔颌面部撞击伤致颅脑损伤后内皮素含量和脑水肿的变化

了解颌面部撞击伤与颅脑损伤的关系,内皮素（ＥＴ）与在颅脑损伤发展过程中的作用。实验兔２５只,分别以平均速度８ｍ／ｓ和３ｍ／ｓ的撞击头致颌面部２,伤后早期观察颌面部和颅脑伤情,分析脑损伤发生条件。取脑组织标本光镜及电镜观察,研究颅脑损伤特点,测定血浆和脑组织中ＥＴ含量及脑含水量。颌面部撞击作国后脑组织病理改变明显,伤后血浆和脑组织匀浆中ＥＴ含量显著提高,出现脑水肿,高速组变化更显著。内皮素含量变化与     

冷冻伤性脑水肿的发生机制及尼莫地平治疗作用的实验研究

目的研究大鼠冷冻伤性脑水肿不同时间脑组织伊文思兰（ＥＢ）、突触体内［Ｃａ２＋］ｉ及Ｃａ２＋－ＡＴＰ酶活性变化与脑含水量变化之间的规律，以探讨冷冻伤性脑水肿的发生机制和类型。方法干湿法测定脑组织水分含量，甲酰胺法测定ＥＢ含量，Ｆｕｒａ－２／ＡＭ荧光标记法测定突触体内［Ｃａ２＋］ｉ，微量定磷法测定线粒体Ｃａ２＋－ＡＴＰ酶活性。采用尼莫地平进行治疗，研究其对ＥＢ含量、［Ｃａ２＋］ｉ、Ｃａ２＋－ＡＴＰ酶活性和脑水肿的影响。结果冷冻伤后３０分钟即已发生Ｃａ２＋超载，伴随Ｃａ２＋－ＡＴＰ酶活性下降及脑组织水分含量及ＥＢ含量增加。尼莫地平治疗后ＥＢ含量和［Ｃａ２＋］ｉ明显下降，而Ｃａ２＋－ＡＴＰ酶活性明显恢复，脑水肿明显减轻。结论ＢＢＢ的通透性增加和细胞内钙通道开放，钙离子浓度超载在脑水肿的发生与发展过程中起了重要作用。冷冻伤性脑水肿在早期既有细胞毒性脑水肿，又有血管源性脑水肿，即混合性脑水肿。     

冷冻伤性脑水肿钙—ATP酶活性变化与脑水肿的关系

目的：研究大鼠冷冻伤性脑水肿后线粒体钙－ＡＴＰ酶活性变化与脑水肿的关系，同时应用尼莫地平干预，观察其对神经细胞钙－ＡＴＰ酶活性和脑水肿的影响．方法：测定线粒体内钙－ＡＴＰ酶活性，干湿法测定脑组织含水量的改变．结果：冷冻伤后３０分钟，线粒体钙－ＡＴＰ酶活性显著下降，４小时和２４小时组钙－ＡＴＰ酶活性持续进行性下降；相反脑组织水份含量则明显增高．应用尼莫地平干预，钙－ＡＴＰ酶活性明显回升，脑水肿则显著减轻．结论：冷冻伤后线粒体内钙－ＡＴＰ酶活性下降与脑组织水份含量增高密切相关，尼莫地平通过升高线粒体内钙－ＡＴＰ酶活性等，可明显减轻脑水肿     

镧示踪法观察大鼠颅脑损伤后血脑屏障形态学变化

目的：颅脑损伤后血脑屏障（ｂｌｏｏｄ－ｂｒａｉｎｂａｒｒｉｅｒ，ＢＢＢ）通透性的变化，是导致外伤性脑水肿的最直接的因素．研究脑ＢＢＢ改变对探讨颅脑损伤脑水肿发生发展过程有重要意义．方法：本实验采用镧示踪法观察大鼠脑损伤后ＢＢＢ超微结构的变化，同时定量检测了伤区脑组织脑水肿发展过程．结果：研究发现伤后１０分钟组，已可见ＢＢＢ开放，伤后２４～４８小时组渗出最为严重，伤后７天组ＢＢＢ功能尚未完全恢复．颅脑损伤后伤区脑组织伊文氏蓝（ｅｖａｎｓｂｌｕｅ，ＥＢ）含量及伤区脑组织含水量的变化过程与ＢＢＢ的改变相一致．结论：对颅脑损伤后脑水肿的治疗应从早期开始，并持续１周以上．     

大鼠颅脑液压损伤后脑组织内Na^＋—K^＋—ATP酶活性的变化

目的：测定大鼠颅脑液压损伤后脑组织内Ｎａ＋－Ｋ＋－ＡＴＰ酶活性，探讨其在继发性脑损伤中的作用。方法：利用大鼠颅脑液压损伤模型，在致伤后６小时测定脑组织含水量、脑组织内Ｎａ＋－Ｋ＋－ＡＴＰ酶活性。结果：脑损伤６小时后，损伤侧脑组织内含水量明显增加（Ｐ＜０．０５），Ｎａ＋－Ｋ＋－ＡＴＰ酶活性明显下降（Ｐ＜０．０５）；而未损伤侧脑组织含水量和脑内Ｎａ＋－Ｋ＋－ＡＴＰ酶活性均无显著改变（Ｐ＞０．０５）。结论：脑损伤后脑组织内Ｎａ＋－Ｋ＋－ＡＴＰ酶活性下降是继发性脑损害发生和发展的重要因素之一。     

严重烧伤后内皮细胞损伤及其在早期脏器损害发病中的作用

３０％Ⅲ度烧伤兔伤后血浆渗透压下降，ＣＥＣ及ＡＣＥ活性升高，血管内皮细胞明显形态学改变，表明伤后内皮细胞受损。缺氧、烧伤血清、ＴＮＦ、内毒素、ＦＰＡＢ及活化粒细胞能损伤培养的人脐静脉内皮细胞。３０％Ⅲ度烧伤大鼠伤后血浆ＥＴ－１明显增多，ＥＴ－１、ＥＴＡ、ＥＴＢ、ｍＲＮＡ于心肺肝肾的表达，于伤后斑点杂交与原位杂交的结果，均表明其明显增强。烧伤内皮素增加，不但使血管收缩，而且增加内皮细胞透性。采用细胞     

基质金属蛋白酶-9在大鼠弥漫性脑损伤中表达及与脑水肿相关性研究

目的 观察大鼠弥漫性脑损伤中基质金属蛋白酶（matrix metalloproteinase，MMP）-9mRNA表达和脑水肿的变化，探讨二者之间的关系。方法 建立Marmarou大鼠弥漫性脑损伤模型，实时荧光定量逆转录-聚合酶链反应测定伤后不同时间MMP-9mRNA的表达，干湿重法测定脑含水量并观察脑组织中炎症反应和毛细血管超微结构变化。结果 外伤后1h大鼠脑组织中MMP-9mRNA开始增加，伤后12h达到高峰并持续7d（P＜0．01），14d下降至对照组水平（P＞0．05）。脑组织含水量比似手术组明显增加，炎性反应和毛细血管的超微结构破坏更重。结论大鼠外伤后诱导MMP-9mRNA表达增加，可能参与了弥漫性脑损伤后血管源性脑水肿的形成，从而加重了继发性脑损伤。     

鞘内注射ETAR拮抗药对大鼠骨癌疼痛改善情况及其对ERK通路的影响

 目的 观察鞘内注射内皮素A受体(ETAR)拮抗药对大鼠骨癌疼痛(BCP)改善作用及其对细胞外调节蛋白激酶(ERK)通路的影响。方法 取60只大鼠均进行鞘内置管,随机分为假手术(sham)组、假手术+ETAR拮抗药(sham+BQ123)组、骨癌痛(BCP)组、骨癌痛+ETAR拮抗药(BCP+BQ123)组。BCP组、BCP+BQ123组采用股骨远端骨髓腔内接种Walker256细胞法建立BCP大鼠模型,sham组、sham+NS同法注射等量生理盐水。建模成功大鼠于建模第14 天,BCP+BQ123组和sham+BQ123组各14只,鞘内注射7 μl BQ123;BCP组13只、sham组14只鞘内注射等量生理盐水。鞘内注射前即刻、注射后0.5、1.0、1.5、2.0、2.5、3.0 h分别评估各组大鼠疼痛行为学:机械性缩足反射阈值(PWT)、自发抬足次数(NSF);末次评估疼痛行为学后,影像学评估各组骨质破坏情况;RT-qPCR、Western blot法检测脊髓组织中内皮素1(ET1)、ETAR、ERK1/2 mRNA和蛋白表达量及p-ERK1/2蛋白表达量。结果 与sham组、sham+BQ123组比较,注射前BCP组、BCP+BQ123组的PWT降低和NSF增多(P<0.05),鞘内注射后T0.5~3.0 h期间,BCP组的PWT和NSF均保持不变,而BCP+BQ123组的PWT先升高后降低,NSF先减少后增多,PWT和NSF均于1.5 h达到最高和最少,3.0 h恢复至注射前水平。胫骨骨质X线片显示,sham组和sham+BQ123组胫骨骨质密度均匀、骨皮质连续无缺失;BCP组注射后14 d出现大范围骨破坏、骨皮质缺损严重;BCP+BQ123组股骨远端见较小骨破坏病灶,部分皮质缺损。与sham组、sham+BQ123组比较,BCP组、BCP+BQ123组脊髓ET1、ETAR mRNA和蛋白及p-ERK1/2蛋白相对表达量均升高,且BCP+BQ123组低于BCP组,差异有统计学意义(P<0.05)。结论 BCP疼痛反应与脊髓ET-1及ETAR有关,鞘内注射ETAR拮抗药可有效减轻BCP大鼠的疼痛反应,可能通过抑制脊髓ERK通路发挥调控作用。     

Early perfusion after controlled cortical impact in rats: quantification by arterial spin-labeled MRI and the influence of spin-lattice relaxation time heterogeneity.

Early posttraumatic cerebral hypoperfusion is implicated in the evolution of secondary damage after experimental and clinical traumatic brain injury (TBI). This is the first report of cerebral blood flow (CBF) measurement by continuous arterial spin-labeled magnetic resonance imaging (MRI) early after TBI in rats using the controlled cortical impact (CCI) model. CCI reduced CBF globally at approximately 3 hr (versus normal), with 85% and 49% reductions in a contused cortical region and contralateral cortex, respectively. In contrast, a prior MRI study from this laboratory showed at 24 hr post trauma a focal CBF reduction restricted to the injury site. In vivo spin-lattice relaxation time (T(1obs)), which is used in CBF quantification, was spatially heterogeneous early after CCI, a time when edema is developing in injured brain tissue. At 4.7 T, T(1obs) values are increased 29% in the contusion (versus normal), consequently reducing CBF quantification to a similar degree. MRI should facilitate coupling posttraumatic CBF with long-term functional outcome. Magn Reson Med 42:673-681, 1999.     

实验性脑出血周围组织脑血流变化与脑水肿形成的相关研究

目的 探讨血肿周围组织脑水肿形成机制及其与局部脑血流变化间的关系，为脑出血临床救治提供实验基础。方法 雄性大鼠70只，随机数字抽样法分为注血组和对照组，分别将40山新鲜自体血或生理盐水通过微量注射泵注入大鼠脑右侧尾状核制备脑出血模型，利用CT灌注成像对大鼠脑出血模型进行动态增强扫描，通过计算机辅助脑灌注成像软件制作大鼠脑CT灌注参数图，对血肿周围局部脑血流量（regional cerebral blood flow，rCBF）、局部脑血容量（regional cerebral blood volume，rCBV）和对比剂平均通过时间（mean transit time，MTT）脑灌注参数进行相对值（病侧／健侧）测量，并与血肿周围脑组织水含量进行相关性分析。结果 大鼠脑注血后血肿周围组织存在低灌注梯度，血肿周围rCBF呈波动性改变，注血后1h rCBF降至最低，以后逐渐回升，分别于注血后6h和24h2次回升至峰值，并随后再度下降；血肿周围rCBV在注血后1h降至最低，随后逐渐增加，并于注血后24h增加至峰值；血肿周围脑组织水含量在注血后24h最高，并延续至72h；血肿周围脑组织水含量与血肿边缘区rCBV具有明显相关性，r=0．372（单侧），P〈0．05。结论 血肿周围组织脑水肿的形成是血脑屏障破坏、细胞毒性水肿及渗透性活性物质共同作用的结果，脑出血早期rCBF下降以及rCBV代偿性增加在脑出血血管源性脑水肿形成中发挥着重要作用，CT灌注成像是活体下研究血肿周围脑血流变化与脑水肿形成机制较为理想的方法。     

Regional differences in distribution volume of I-123 IMP in the human brain: Effect on CBF calculated by ARG method

OBJECTIVE: Two methods of quantitating cerebral blood flow (CBF) with iodine-123-labeled N-isopropyl-p-iodoamphetamine (I-123 IMP) and a two-compartment model had been proposed; one is the table look-up (TLU) method and the other is the autoradiographic (ARG) method. The TLU method provides values of the cerebral blood flow (CBF) values and distribution volume of I-123 IMP (Vd) independently. In the ARG method, a fixed Vd is applied for the entire brain to calculate CBF. Our purpose was to evaluate regional differences in Vd in the human brain, or possible effects of regional differences in Vd on CBF calculated by the ARG method. METHODS: In the present study, two SPECT scans were acquired from each of eight normal subjects (aged 44.0 +/- 16.7) at 40 min and 180 min of mid-scan-time after intravenous 1 min infusion of 111 MBq IMP. A single arterial blood sampling was performed 10 min after the IMP infusion. All images were anatomically normalized and analyzed with SPM99 and Matlab. We generated CBF and Vd images for each subject by the TLU method and evaluated differences in Vd among brain structures. We subsequently generated another set of CBF images by the ARG method and examined differences between CBF calculated by the TLU method and that by the ARG method. RESULTS: Significant main effects of subject and brain structure in Vd were observed (two-way ANOVA). Vd values were higher in the deep gray matter than in the cerebral cortical regions. Among the cerebral cortical regions, no significant difference in Vd was observed. In spite of the significant differences in Vd among the brain structures, the voxel-by-voxel analyses as well as the ROI analyses revealed no statistically significant difference between CBF calculated by the TLU method and that by the ARG method. CONCLUSIONS: Although regional differences in Vd were observed, the present results support the assumption that a fixed Vd does not cause significant error in the calculation of CBF by the ARG method.     

大鼠颅脑爆炸伤后水通道蛋白4的表达变化

目的 研究大鼠颅脑爆炸伤后水通道蛋白4（aquaporin 4，AQP4）表达变化及其与脑水肿的关系。方法Wistar成年大鼠96只随机分为爆炸伤组和假手术组（各48只），右侧颞顶部开直径为1cm的骨窗后用80mgTNT电雷管在5cm垂直距离爆炸，于伤后4，12h、1，2，5，7d分别检测损伤区脑含水量，病理学变化、血脑屏障通透性改变、AQP4 mRNA和蛋白的表达变化。结果爆炸伤后损伤区脑含水量呈进行性增加，并于伤后2d达高峰。AQP4的表达也明显升高，开始局限于损伤中心，而后增高的区域扩大，AQP4表达增高的区域与光、电镜下脑水肿区域一致，单位面积表达的量于伤后2d出现峰值，之后有所下降，但直到第7天其表达的量仍高于假手术组（P〈0．05），且与脑含水量呈正相关。爆炸伤后4h和12h，伊文思蓝渗出主要局限于损伤中心，随时间延长，尽管脑水肿程度加重，但伊文思蓝渗出范围无明显扩大。结论爆炸伤早期以血管源性脑水肿为主要表现，继发性细胞毒性脑水肿可能是爆炸伤后期脑水肿的主要原因，AQP4表达增加参与了爆炸伤后细胞毒性脑水肿的形成过程。     

颅脑爆震伤后兔脑内代谢变化的磁共振波谱研究

目的 利用磁共振波谱技术探讨颅脑爆震伤后不同时间段脑局部代谢变化.方法 新西兰大白兔45只采用随机数字表法分为对照组(10只)和创伤组(35只),采用600 mgTNT当量纸雷管在创伤组兔脑上方约6.5 cm垂直距离爆炸,于伤后1,6,12,24 h、3,7,14 d用磁共振波谱技术观测动物存活情况,并检测脑损伤区病理及磁共振波谱表现,观察乙酰天门冬氨酸(N-acetylaspartate,NAA)/肌酸(creatine,Cr)、胆碱(choline,Cho)/Cr在爆震伤后随时间发展的演变过程.结果 创伤组兔存活时间在7 d以上,病理及常规MRI示脑挫伤病灶;NAA/Cr均值在损伤后1 h明显下降,持续至伤后24 h,24 h后义上升,7 d后再次下降.Cho/Cr均值在损伤1 h后即明显升高,12 h后下降,3 d后义逐渐升高.结论 磁共振波谱技术可反映兔颅脑爆炸伤不同时间段局部组织的代谢变化,为了解爆雀伤后局部组织变化情况及判断组织损伤类型提供理论依据.

Abstract：

Objective To evaluate the regional cerebral metabolic changes in different episodes by magnetic resonance spectroscopy (MRS) after explosive brain injury in rabbits. Methods Fortyfive New Zealand white rabbits were randomly divided into eight groups, ie, normal control group( 10 rabbits) and trauma group (35 rabbits). The explosive injury in trauma group was induced by explosion of 600 mg TNT equivalent of paper detonators at 6.5 cm above the rabbit brain. The rabbits in trauma group was divided into 1,6, 12, 24 hours, 3, 7, 14 days subgroups (6 rabbits per group). The survival rate was observed at different time points after explosive injury. The MRS was used to detect the regional cerebral metabolic changes including N-acetylaspartate (NAA)/creatine (Cr) ratio and choline(Cho)/Cr ratio as well as evolution of blast injuries over time. Results The rabbits survived for overseven days in the trauma groups, with typical brain contusion manifested by pathological and conventional MRI. Compared with the normal control group, the NAA/Cr ratio was markedly decreased at one hour after injury, slightly rose again at 24 hours and fell again after seven days. The Cho/Cr ratio was markedly increased at one hour after injury, slightly fell again at 12 hours and rose again at three days after injury.Conclusions MRS can manifest the regional cerebral metabolic changes of rabbits with explosive injury at different time points and hence provide a theoretical basis for understanding the local tissue changes and determining the type of tissue damage after blast injury.     

Et-A receptor antagonist BQ123 prevents radiocontrast media-induced renal medullary hypoxia

Purpose:
Renal vasoconstriction with resultant tissue hypoxia, especially in the renal medulla, has been suggested to play a role in contrast media (CM)-induced nephropathy. Endothelin (ET) is released into the blood stream following CM injection and has been proposed as a potential mediator through its vasoconstrictive properties. Material and Methods:
To investigate the possible protective influence of ET-receptor antagonists against CM-induced reduction in renal function, we studied the effects of injection of iopromide with and without pretreatment with BQ123 (ET-A antagonist) or BQ788 (ET-B antagonist) on renal superficial cortical flow (CBF), outer medullary blood flow (OMBF) and outer medullary oxygen tension ( pO₂) in normal rats. Results:
Administration of CM (1600 mg I/kg b.w.) did not affect CBF in any of the groups. However, a transient decrease in OMBF occurred, which was unaffected by both BQ123 and BQ788. Also a transient decrease in outer medullary pO₂ was induced by CM administration. The pO₂ reduction was significantly smaller after pretreatment with BQ123, than after injection of CM alone or together with BQ788, and pO₂ returned more rapidly to the control level. Neither receptor antagonist had an effect on CM-mediated increases in electrolyte excretion. Conclusion: 
In the normal rat, activation of ET-A receptors is partly involved in the depression of outer medullary pO₂ caused by injection of iopromide. However, the decrease in OMBF after iopromide injection is not mediated by ET receptors. The beneficial effects of the ET-A receptor antagonist on CM-induced changes in outer medullary pO₂ seem therefore not primarily mediated on the hemodynamic level but may rather involve tubular transport mechanisms.