内皮素一氧化氮在蛛网膜下腔出血后脑血管痉挛中的动态变化

目的：探讨内皮素（ＥＴ－１）和一氧化氮（ＮＯ）代谢产物在蛛网膜下腔出血（ＳＡＨ）后症状性脑血管痉挛（ＳＣＶＳ）发生机制中的作用。方法：建立兔的症状性脑血管痉挛模型,观察ＳＡＨ后不同时间血浆和脑脊液（ＣＳＦ）中ＥＴ－１和ＮＯ代谢产物含量变化。结果：ＳＡＨ后第４天和第７天血浆和ＣＳＦ中ＥＴ－１含量均显著升高（Ｐ〈０．０１）。且以ＳＡＨ后第４天为著。ＳＡＨ后第４天和第７天血浆和ＣＳＦ中ＮＯ代谢产物含量也明显升高（Ｐ〈０．０１）,但二者之间无显著性差异（Ｐ〉０．０５）。结论：ＳＡＨ后血浆和ＣＳＦ中ＥＴ－１和ＮＯ代谢产物含量增加在ＳＣＶＳ发生机制中起重要作用。     

实验性脑血管痉挛时一氧化氮与超氧化物歧化酶对脑血流的作用研究

目的 探讨一氧化氮（ＮＯ）、超氧化物歧化酶（ＳＯＤ）分别及联合使用对大鼠实验性蛛网膜下腔出血（ＳＡＨ）后脑血管痉挛（ＣＶＳ）时脑血流（ＣＢＦ）的作用。方法 将３０只大鼠随机分成５组（每组６只）。Ａ组：假手术＋盐水,Ｂ组：ＳＡＨ＋盐水;Ｃ组：ＳＡＨ＋ＳＯＤ;Ｄ组：ＳＡＨ＋ＮＯＣ１２;Ｅ组：ＳＡＨ＋ＳＯＤ、ＮＯＣ１２。模拟制成４８ｈ后,通过Ｌａｓｅ－Ｄｏｐｐｌｅｒ血液仪观察各种药物持续静脉注射１ｈ内Ｃ     

遗传性运动感觉性神经病合并肥厚性心肌病的3D—TCD,rCBF,BAEP…

目的了解遗传性运动感觉性神经病（ＨＭＳＮ）合并肥厚心肌病（ＨＣＭ）的经颅多普勒（ＴＣＤ）局部脑血流量（ｃＣＢＦ），脑干听觉诱发电位（ＢＡＥＰ）和心电图（ＥＣＧ）的变化。方法，对一家三代ＨＭＳＮ合并ＨＣＭ１２例患者和１例无症状者常规进行了这四项检查，结果ＴＣＤ，ｒＣＢＦ，ＢＡＥＰ和ＥＣＧ的异常率分别为８５％，７６％，９２％和９２％。结论绝大多烽ＨＭＳＮ合并ＨＣＭ患者的ＴＣＤ，ｒＣＢＦ，ＢＡＥＰ和ＥＣ     

动物蛛网膜下腔出血后脑血管痉挛与内皮素、一氧化氮的关系

目的:研究兔症状性蛛网膜下腔出血(ＳＡＨ)后脑血管痉挛(ＣＶＳ)与内皮素(ＥＴ)和一氧化氮(ＮＯ)的关系。方法:采用兔ＳＡＨ模型,观察ＳＡＨ前后动物进食量、神经功能和局部脑血流量(ｒＣＢＦ)改变,测定血液和脑脊液中ＥＴ和ＮＯｘ－含量。结果:ＳＡＨ后动物进食量和ｒＣＢＦ下降、神经功能障碍,血液和脑脊液中ＥＴ含量增加,ＮＯｘ－含量下降(Ｐ＜０．０１)。结论:兔双侧颈动脉结扎后枕大池二次注血可制成可靠的症状性ＳＡＨ后ＣＶＳ模型。ＳＡＨ后ＥＴ和ＮＯ含量的改变与ＣＶＳ的发生密切相关,并进而导致临床症状的恶化。     

神经节苷脂对缺血性大鼠脑保护作用的研究

目的探讨神经节苷脂（ＧＭ１）的脑保护作用及其可能机制。方法用四血管闭塞（４ＶＯ）全脑缺血再灌注模型,用高效液相色谱仪柱前衍生色谱法测定假手术组、缺血３０ｍｉｎ再灌注６０ｍｉｎ生理盐水（ＮＳ）处理组、缺血３０ｍｉｎ再灌注６０ｍｉｎＧＭ１处理组的海马组织兴奋性氨基酸（ＥＡＡ）含量,并观察缺血３０ｍｉｎ再灌注４ｄ海马ＣＡ１区病理变化。结果缺血再灌注ＮＳ处理组海马组织ＥＡＡ含量显著性降低（Ｐ＜０．０１）,海马ＣＡ１区多数神经元坏死,残存神经元呈较严重缺血性改变,ＧＭ１处理组上述生化病理改变明显为轻。结论推测ＧＭ１可调控缺血再灌注早期ＥＡＡ的过度释放和（或）重摄取受阻,减轻其在细胞外堆聚引起的兴奋毒性损伤,具有脑保护作用。     

缺血性脑中风患者高压氧治疗价值及机理探讨

目的　了解高压氧治疗缺血性脑中风的治疗价值及机理。方法　对 ４７ 例急性缺血性中风患者用高压氧（ Ｈ Ｂ Ｏ）治疗前后测定 ｒ Ｃ Ｂ Ｆ及检查脑电图的变化。结果　治疗后 Ｈ Ｂ Ｏ 组患者 ｒ Ｃ Ｂ Ｆ 值均较治疗前明显降低（灰质重于白质，病灶侧重于非病灶侧）；而对照组患者 ｒ Ｃ Ｂ Ｆ值较治疗前明显增加（ Ｐ＜ ０．０５）。治疗后 Ｈ Ｂ Ｏ 组 Ｅ Ｅ Ｇ 频率虽较治疗前增快，慢波减少，但无统计学意义；而对照组 α指数，波频改善显著，慢波明显减少（ Ｐ＜ ０．０５）。结论　 Ｈ Ｂ Ｏ 治疗不仅可使正常脑组织血管收缩，脑血流量减少，而对缺血性损害侧大脑半球的血管收缩更为显著，有加重“脑盗血”发生、发展的趋势。     

碱性成纤维细胞生长因子对脑缺血后神经元特异性烯醇化酶的影响

目的研究碱性成纤维细胞生长因子（ｂＦＧＦ）对局灶脑缺血的作用。方法采用线栓法制备右侧大脑中动脉闭塞局灶性脑缺血模型。术后即刻分别腹腔注射ｂＦＧＦ和生理盐水。测定缺血前后血压、心率，缺血前、缺血后３０分钟～２４小时的局部脑血流量（ｒＣＢＦ），缺血２４小时血清神经元特异性烯醇化酶（ＮＳＥ），观察缺血２４小时病理学改变和行神经功能评分。结果发现ｂＦＧＦ可降低血清ＮＳＥ，改善组织病理和ｒＣＢＦ，促进神经功能恢复，但不影响血压、心率。结论ｂＦＧＦ能减轻缺血性脑损害，保护脑组织。     

载脂蛋白E与脑动脉硬化症

本文观察７８例脑动脉硬化症患者与对照组４４例，对其血清载脂蛋白Ｅ（ＡＰＯＥ）和高密度脂蛋白（ＨＤＬ－Ｃ）、低密度脂蛋白（ＬＤＬ－Ｃ）、胆固醇（ＴＣ）、甘油三脂（ＴＧ）、载脂蛋白ＡＩ（ＡＰＯＡＩ）、载脂蛋白Ｂ（１００）（ＡＰＯＢ（１００））进行含量测定，并将ＡＰＯＥ与ＨＤＬ－Ｃ、ＬＤＬ－Ｃ、ＴＣ、ＴＧ、ＡＰＯＡＩ、ＡＰＯＢ（１００）逐一进行相关比较，结果发现：脑动脉硬化症病人（ＣＡＳ）血清ＡＰＯＥ、ＬＤＬ－Ｃ、ＴＣ、ＴＧ、ＡＰＯＢ（１００）明显高于正常对照组（Ｐ＜０．０１），ＨＤＬ－Ｃ显著低于正常对照组（Ｐ＜０．０１），ＡＰＯＡＩ无明显变化（Ｐ＞０．０５），且ＡＰＯＥ与ＨＤＬ－Ｃ呈负相关；与ＬＤＬ－Ｃ、ＴＣ、ＴＧ、ＡＰＯＢ（１００）呈正相关；与ＡＰＯＡＩ无直线相关关系。提示ＡＰＯＥ可做为诊断脑动脉硬化症的重要指标。     

兔MCAO后脑组织NOS活性的变化

一氧化氮（ＮＯ）与脑缺血关系密切，对缺血性脑损害可能有直接的影响，一氧化氮的合成酶（ＮＯＳ）是ＮＯ生物合成的限速酶，本文在建立兔ＭＣＡＯ局灶脑缺血模型基础上，测定缺血后不同时间缺血区和正常脑组织的ＮＯＳ活性。结果证实缺血后早期（ＭＣＡＯ后１ｈ内）ＮＯＳ活性突然升高。     

β淀粉样蛋白诱导脑内神经元凋亡的研究

目的 探讨凋亡机制在β－淀粉样蛋白（β－ａｍｙｌｏｉｄ ｐｒｏｔｅｉｎ,Ａβ）脑内致病作用中的意义。方法 用微量注射器将Ａβ１－４０注射到大鼠右侧海马Ｃ工区诱发Ａβ在脑内该区域的沉积。７天后,用ＨＥ染色、ＴＵＮＥＬ法及透射电镜检测该区细胞凋亡,用免疫组化ＳＡＢＣ法检测Ｂａｘ／Ｂｃｌ－２的表达。结果 在Ａβ组右侧少我ＨＥ１区ＨＥ、ＴＵＮＥＬ染色及电镜均发现大量凋亡细胞,而假手术对照组和生理盐水对照组     

大鼠蛛网膜下腔出血血清、脑组织一氧化氮变化与脑缺血损害

目的:探讨一氧化氮(NO)在蛛网膜下腔出血(SAH)缺血性脑损害中作用。方法:应用非开颅大鼠模型,观察24h内脑微区血流量(CBF)和颅内血清及脑组织NO水平动态改变,3d后对海马CA1区行病理检查。结果:SAH后CBF和血清NO降低,脑组织NO增加,海马CA1区神经元明显受损。结论:血清NO减少、脑组织NO增加与SAH脑缺血损害的发生,发展有密切关系。     

Role of HCN channels in neuronal hyperexcitability after subarachnoid hemorrhage in rats

Disruption of ionic homeostasis and neuronal hyperexcitability contribute to early brain injury after subarachnoid hemorrhage (SAH). The hyperpolarization-activated/cyclic nucleotide (HCN)-gated channels play critical role in the regulation of neuronal excitability in hippocampus CA1 region and neocortex, in which the abnormal neuronal activities are more readily provoked. This study was to investigate the interactions between HCN channels and hyperneuronal activity after experimental SAH. The present results from whole-cell recordings in rat brain slices indicated that (1) perfusion of hemoglobin (Hb)-containing artificial CSF produced neuronal hyperexcitability and inhibited HCN currents in CA1 pyramidal neurons, (2) nitric oxide/Spermine (NO/Sp), a controlled releaser of nitric oxide, attenuated neuronal excitability and enhanced HCN currents in CA1 pyramidal neurons, while L-nitroarginine (L-NNA), an inhibitor of nitric oxide synthase, reduced the HCN currents; and (3) the inhibitory action of Hb on HCN currents was reversed by application of NO/Sp, which also reduced neuronal hyperexcitability; conversely, L-NNA enhanced inhibitory action of Hb on HCN currents. Additionally, Hb perfusion scavenged the production of nitric oxide and decreased the expression of HCN1 subunits in CA1 region. In the rat SAH model, the expression of HCN1, both at mRNA and protein level, decreased in hippocampus CA1 region at 24 h and more pronounced at 72 h after SAH. These observations demonstrated a reduction of HCN channels expression after SAH and Hb reduced HCN currents in hippocampus CA1 pyramidal neurons. Inhibition of HCN channels by Hb may be a novel pathway for inducing the hyperneuronal excitability after SAH.     

脑血管痉挛大鼠脑微区血流量和血浆内皮素1观察

应用非开颅大鼠蛛网膜下腔出血(SAH)模型,观察24h内脑微区血流量和颅内血清内皮素1(ET1)动态变化,并测量基底动脉(BA)管径。发现SAH后脑微区血流量迅速降低,1h达最低值,24h内无明显恢复趋势。SAH后1h开始至24h血浆ET1浓度显著增高。SAH后0.5h BA管径明显缩小。结果提示SAH后ET1的增多与脑血管痉挛及其缺血性脑损害的产生有关。     

Effects of S-nitrosoglutathione on acute vasoconstriction and glutamate release after subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: Subarachnoid hemorrhage (SAH) causes acute vasoconstriction that contributes to ischemic brain injury shortly after the initial bleed. It has been theorized that decreased availability of nitric oxide (NO) may contribute to acute vasoconstriction. Therefore we examined the effect of the NO donor N-nitroso glutathione (GSNO) on acute vasoconstriction and early ischemic glutamate release after experimental SAH. METHODS: SAH was induced by the endovascular suture method in anesthetized rats. GSNO (1 micromol/L/kg, n=31) or saline (n=21) was injected 5 minutes after SAH. Sham-operated rats received GSNO (1 micromol/L/kg, n=5) 5 minutes after sham surgery. Arterial and intracranial pressures, cerebral blood flow (CBF), and extracellular glutamate release were measured serially for 60 minutes after SAH. SAH size was determined, and vascular measurements were made histologically. RESULTS: GSNO had no effect on resting blood pressure, intracranial pressure, cerebral perfusion pressure, or CBF in sham-operated animals. However, administration of GSNO after SAH was associated with significantly increased CBF (161.6+/-26.6% versus saline 37.1+/-5.5%, 60 minutes after SAH, P<0.05), increased blood vessel diameter (internal carotid artery [ICA] 285.0+/-16.5 microm versus saline 149.2+/-14.1 microm, P<0.01), decreased vessel wall thickness (ICA12.9+/-0.7 microm versus saline 25.1+/-1.6 microm, P<0.01), and decreased extracellular glutamate levels (3315.6+/-1048.3% versus saline469. 7+/-134.3%, P<0.05). Blood pressure decreased transiently, whereas intracranial pressure, cerebral perfusion pressure, and SAH size were not affected. CONCLUSIONS: These results suggest that GSNO can reverse acute vasoconstriction and prevent ischemic brain injury after SAH. This further implies that acute vasoconstriction contributes significantly to ischemic brain injury after SAH and is mediated in part by decreased availability of NO.     

癫痫持续状态大鼠脑损害及血清烯醇化酶的变化及意义

目的观察大鼠致痫后血清烯醇化酶(neuron specifi cenolose,NSE)水平变化及海马组织病理学改变。方法采用氯化锂-匹罗卡品联合腹腔注射制成大鼠癫痫持续状态模型(status epileptitus,SE)。用放射免疫法分别对对照组、地西泮干预组、实验组SE后不同时间点血清中NSE水平及常规病理变化进行观测。结果血清NSE水平在大鼠SE后6h开始升高,24~48h达高峰,72h开始下降,1周后趋于正常;实验组血清NSE水平的动态变化与对照组和干预组比较有统计学意义(P<0.05),而且常规病理也可见海马区神经元变性、坏死性改变,以CA1、CA3区及颞叶皮层为重。而对照组和地西泮干预组之间血清NSE水平比较无统计学意义(P>0.05),也无病理形态学变化。结论大鼠SE后可引起脑组织损害,以CA1、CA3区及颞叶皮层损害为主。血清NSE水平是反映神经元损伤的客观生化指标。     

Time-Course Alterations of Monoamine Levels and Cerebral Blood Flow in Brain Regions after Subarachnoid Hemorrhage in Rats

To investigate the possible correlation between changes in monoaminergic neuronal activity and cerebral blood flow (CBF) in the same brain regions after subarachnoid hemorrhage (SAH), monoamine levels were analyzed by both HPLC-ECD and fluorohistochemistry techniques, and CBF was measured by using colored microspheres. At the second day of SAH, significant and nonsignificant reductions in blood flow were seen in the examined brain regions with a marked increase in CBF appearing in the telencephalon and hypothalamus on the third day. Significant reductions of monoamine levels in most brain regions were also observed on the second day after SAH, whereas norepinephrine (NE) levels in midbrain increased to 1.5 times compared to the normal level. These reductions were sustained until the fourth day of SAH, although at the third day, serotonin (5-HT) and dopamine levels in the hippocampus and 5-HT levels in the cerebellum were significantly elevated. In fluorohistochemical studies, the fluoro-intensities of monoamines, particularly catecholamines, in the midbrain dorsal NE bundle were enhanced at the second day after SAH. These NE neurons originated from the A6 cell group close to the area where homologous blood was applied through the cisterna magna. The results obtained after SAH show an apparent correlation between changes in monoamine levels and CBF in norepinephrine (NE)-rich areas. These results suggest that SAH-induced neuronal dysfunctions, particularly with NE neurons, are caused not only by reductions of blood flow but also by hemorrhage.     

Ischemia-induced changes of platelet endothelial cell adhesion molecule-1 in the hippocampal CA1 region in gerbils

We observed chronological changes of platelet endothelial cell adhesion molecule-1 (PECAM-1), final mediator of neutrophil transendothelial migration, immunoreactivity, and protein level in the gerbil hippocampus proper after 5 min of transient ischemia. One day after ischemic insult, PECAM-1 immunoreactivity and protein level increased slightly in the hippocampus proper. Thereafter, PECAM-1 immunoreactivity and protein level increased significantly in the hippocampus proper by 4 days after ischemic insult. Especially, PECAM-1 in the hippocampal CA1 region was higher than that in the CA2/3 region. Five days after ischemic insult, PECAM-1 immunoreactivity decreased compared to the 4 days post-ischemic group. However, the RNA levels of PECAM-1 in the hippocampus proper were significantly decreased in the 4 days post-ischemic groups compared to that in the sham-operated group. This result suggests that the increase of PECAM-1 and decrease of PECAM-1 RNA in the CA1 region 4 days after ischemia may be associated with transmigration of neurotrophil.     

阿司匹林对沙土鼠全脑缺血-再灌注后脑内一氧化氮合酶及一氧化氮的影响

目的观察阿司匹林对沙土鼠全脑缺血-再灌注后的脑保护作用及其与脑内一氧化氮合酶及一氧化氮水平变化的关系。方法采用夹闭双侧颈总动脉的方法,制备沙土鼠短暂性全脑缺血-再灌注模型。27只健康雄性蒙古沙土鼠随机分为假手术组、脑缺血-再灌注组和阿司匹林治疗组,观察缺血7min再灌注24h后沙土鼠脑组织的病理学改变,以及一氧化氮合酶与一氧化氮水平的变化。结果病理学检查结果显示,沙土鼠脑缺血7min再灌注24h后海马CA1区缺血性损害明显,脑组织内一氧化氮合酶及一氧化氮水平显著升高(P<0.01);与脑缺血-再灌注组相比,阿司匹林治疗组沙土鼠的病理损害较轻,一氧化氮合酶与一氧化氮水平明显下降(P<0.01)。结论阿司匹林可显著减轻脑缺血-再灌注后的脑损伤,其作用机制可能与抑制一氧化氮合酶与一氧化氮水平上升有关。     

Expression and changes of galanin in neurons and microglia in the hippocampus after transient forebrain ischemia in gerbils

In the present study, we investigated chronological changes of galanin (GAL), well known as the potassium channel opener, immunoreactivity and GAL protein level in the hippocampus of the gerbil at the various times after 5 min transient forebrain ischemia. In the sham-operated group, weak GAL immunoreactivity was found in non-pyramidal cells. At 12 h after ischemia-reperfusion, the number of GAL-immunoreactive neurons and GAL immunoreactivity were significantly increased in the hippocampus compared to 3 h after ischemic insult, especially in the hippocampal CA1 region. Thereafter the number of GAL-immunoreactive neurons and GAL immunoreactivity decrease time-dependently in the hippocampus. Four days after transient ischemia, GAL immunoreactivity was low as compared with the sham-operated group. At this time point after ischemic insult, GAL immunoreactivity was shown in microglia in the CA1 region because delayed neuronal death happened in the CA1 pyramidal cells. The result of Western blot showed the pattern of GAL expression similar to that of immunohistochemical data. These results suggest that the early increase of GAL in the CA1 pyramidal cells may be associated with the reduction of the excitotoxic damage, that long-lasting enhanced expression of endogenous GAL at 12 h-2 days after ischemia may be associated with efflux of potassium ion into the extracellular space, and that GAL expression in microglia 4 days after ischemia may be associated with reduction of ischemic damage.     

Ischemia-induced changes in glucagon-like peptide-1 receptor and neuroprotective effect of its agonist, exendin-4, in experimental transient cerebral ischemia

Glucagon-like peptide-1 receptor (GLP-1R) protects against neuronal damages in the brain. In the present study, ischemia-induced changes in GLP-1R immunoreactivity in the gerbil hippocampal CA1 region were evaluated after transient cerebral ischemia; in addition, the neuroprotective effect of the GLP-1R agonist exendin-4 (EX-4) against ischemic damage was studied. GLP-1R immunoreactivity and its protein levels in the ischemic CA1 region were highest at 1 day after ischemia/reperfusion (I/R). At 4 days after I/R, GLP-1R immunoreactivity was hardly detected in CA1 pyramidal neurons, and its protein level was lowest. GLP-1R protein level was increased again at 10 days after I/R, and GLP-1R immunoreactivity was found in astrocytes and GABAergic interneurons. In addition, EX-4 treatment attenuated ischemia-induced hyperactivity, neuronal damage, and microglial activation in the ischemic CA1 region in a dose-dependent manner. EX-4 treatment also induced the elevation of GLP-1R immunoreactivity and protein levels in the ischemic CA1 region. These results indicate that GLP-1R is altered in the ischemic region after an ischemic insult and that EX-4 protects against ischemia-induced neuronal death possibly by increasing GLP-1R expression and attenuating microglial activation against transient cerebral ischemic damage.