The effect of 2-methoxyestradiol, a HIF-1 alpha inhibitor, in global cerebral ischemia in rats

Global cerebral ischemia is an important clinical problem with few effective treatments. The hippocampus, which is important for memory, is especially vulnerable during global ischemia. Brain-specific knockout of hypoxia inducible factor-1 alpha (HIF-1 alpha) has been shown to be protective in focal ischemia in vivo. 2-methoxyestradiol (2ME2) is a natural metabolite of estrogen that is known to inhibit HIF-1 alpha. We tested 2ME2 in a rat model of global cerebral ischemia. Global ischemia was induced with the two-vessel occlusion model (2VO) which entailed hemorrhagic hypotension to a mean arterial pressure of 38-42 mmHg with simultaneous bilateral common carotid artery occlusion for 8 minutes. Sprague-Dawley rats (male, 280-350 g) were randomly assigned to three groups: global ischemia (GI, n=17), global ischemia with 2ME2 treatment (GI + 2ME2, n=17) and sham surgery (sham, n=12). 2ME2 treatment (15 mg/kg in 1% DMSO) was rendered 10 minutes after reperfusion. Rats in the GI and sham groups received similar doses of the DMSO solvent. Rats were killed 24 hours, 72 hours and 7 days after reperfusion. Quantitative CA1 hippocampal cell counts demonstrated significantly lower cell survival in the GI + 2ME2 group compared to either the GI or sham groups, in spite of a statistically significant reduction in HIF-1 alpha by Western blotting analysis of the GI + 2ME2 group. We conclude that 2ME2 worsens outcomes after global ischemia in rats.     

2ME2对全脑缺血大鼠模型HIF-1α及凋亡相关基因的作用

目的 探讨2-甲氧基雌二醇(2ME2)对全脑缺血大鼠缺氧诱导因子-1α(HIF-1α)及凋亡相关基因的作用. 方法 将成年雄性SD大鼠168只按随机数字表法分为伞脑缺血组(n=84)和全脑缺血2ME2干预组(n=841),然后按再灌注时间不同又分为6h、12h、24h、48h、72h、5d和7d7个亚组.采用改良的Pu刘lsineli 4-VO法制作全脑缺血大鼠模型.应用Nissl染色进行海马神经元计数,免疫组化及RT-PCR技术进行HIF-1α、caspase-3蛋白及RTP801 mRNA表达检测. 结果 全脑缺血2ME2干预组48h至7d亚组神经元计数分别为37.09±3.52、26.93±3.10、22.22±3.091、6.98±3.07.与全脑缺血组相应时间点亚组相比明显增加,差异均有统计学意义(P＜0.05).全脑缺血2ME2干预组48h至7d亚组HIF-1α、caspase-3蛋白表达阳性细胞计数分别为11.47±1.98、20.27±2.07、3.12±0.89、1.07±0.83和12.39±1.67、20.65±2.01、15.6l±1-26、6.57±1.12,与全脑缺血组相应时间点亚组相比明显减少,差异均有统计学意义(P＜0.05).全脑缺血2ME2干预组12h至5d亚组RTP801mRNA表达吸光度比值分别为0.750±0.078、1.008±0.090、0.717±0.072、0.431±0.047、0.231±0.028,与全脑缺血组相应时间点亚组相比明显减低,差异均有统计学意义(P＜0.05). 结论 在全脑缺血急性期,2ME2抑制HIF-1α及凋亡相关基因RTP801、caspase-3的表达,具有一定的神经保护作用.     

亚低温对大鼠短暂全脑缺血后神经元凋亡的影响

目的 探讨亚低温对大鼠脑缺血后神经元凋亡的影响，揭示亚低温的部分神经保护机制。方法 采用“双侧颈总动脉阻断＋全身低血压”方法来建立大鼠短暂性全脑缺血模型。用神经元尼氏体亚甲兰特殊染色法观察大鼠脑缺血后海马CA1区神经元损害情况；原位细胞凋亡检测法（TUNEL染色）及电镜观察脑缺血后CA1区神经元凋亡情况。结果 与假手术组、低温缺血组相比，常温缺血组海马CA1区神经元缺失明显（P＜0．01）。常温及低温缺血组海马CA1区均存在神经元凋亡，但低温缺血组海马CA1区凋亡神经元数明显少于缺血组（P＜0．01）。结论 经“双侧颈总动脉阻断＋全身低血压”方法建立的大鼠短暂全脑缺血模型证实了亚低温的脑保护作用。全脑缺血后的迟发性神经元死亡很可能经由凋亡途径，而亚低温可通过抑制缺血性神经元凋亡而发挥一定的神经保护作用。     

粒细胞集落刺激因子对血管性痴呆大鼠海马神经细胞凋亡的影响

背景：研究发现，粒细胞集落刺激因子可激活脑内成体神经干细胞，刺激其增殖和分化，还能促进脑内各种神经营养因子分泌，减小脑缺血动物模型的缺血灶，促进慢性脑卒中模型缺失神经功能的长期恢复。 目的：观察粒细胞集落刺激因子对血管性痴呆大鼠海马神经细胞凋亡的作用。 方法：采用永久性双侧颈总动脉结扎法建立大鼠血管性痴呆模型，抽签法随机分为4组：实验组(皮下注射粒细胞集落刺激因子干预治疗)、对照组(注射生理盐水)、假手术组(仅行颈前正中切开，不结扎颈总动脉)。采用Morris水迷宫进行定向航行观察大鼠逃避潜伏期，评价大鼠空间学习记忆能力，TUNEL染色和图像分析大鼠海马神经细胞的凋亡。 结果与结论：对照组和实验组大鼠脑缺血后7 d，大鼠平均逃避潜伏期较假手术组明显延长(P < 0.01)，海马组织TUNEL阳性凋亡细胞较假手术组显著增高(P < 0.01)，随着时间的延长，14，28 d时大鼠学习记忆功能障碍逐渐加重，相应海马组织TUNEL阳性凋亡细胞逐渐增加。14，28 d时实验组大鼠平均逃避潜伏期比对照组明显缩短，海马组织TUNEL阳性凋亡细胞也较对照组显著减少。说明脑缺血后早期给予外源性粒细胞集落刺激因子有助于减少海马组织神经细胞的凋亡，改善大鼠学习记忆能力。     

Injection of neural progenitor cells improved learning and memory dysfunction after cerebral ischemia

Accumulating evidence indicates that stem cells have the ability to improve neurological deficits seen after cerebral ischemia. However, the effects of neural progenitor cells (NPCs) on cerebral ischemia-induced learning and memory dysfunction remain to be clarified. The purpose of the present study was to determine whether the injection of exogenous NPCs could prevent learning and memory dysfunction after cerebral ischemia. Sustained cerebral ischemia was produced by the injection of 700 microspheres into the right hemisphere of each rat. We demonstrated that injection of NPCs into the hippocampus at 10 min after the induction of cerebral ischemia reduced prolongation of the escape latency seen in acquisition and retention tests of the water maze task on Days 12-28 after cerebral ischemia. Injection of NPCs partially attenuated the decrease in viable areas of the ipsilateral hemisphere on Day 28 after the cerebral ischemia. We also demonstrated that injection of NPCs prevented the decrease in the level of BDNF seen at the early period after cerebral ischemia. These results suggest that the injection of exogenous NPCs into the hippocampus can prevent cerebral ischemia-induced learning and memory dysfunction, possibly through maintenance of the BDNF level.     

Hippocampal unit activity after transient cerebral ischemia in rats

Single unit activity of CA1 and CA3 neurons in the hippocampus was recorded in rats 1, 2, or 3 days after 10 minutes of transient cerebral ischemia induced by the clamping of both carotid arteries combined with hypotension. In addition, paired pulse inhibition/facilitation of the CA1 population spike was examined on Day 2 using two successive stimuli of the contralateral CA3 region delivered at various intervals. On Day 1, the mean +/- SEM firing rate in the CA1 region was 0.91 +/- 0.42/sec (n = 5), which was not significantly different from the control value of 0.98 +/- 0.26/sec (n = 5). Firing rate increased on Days 2 and 3 to 3.96 +/- 0.69/sec (n = 5), and 6.49 +/- 0.89/sec (n = 5), respectively. In the CA3 region, the mean +/- SEM firing rate of 1.18 +/- 0.27/sec in the five control rats sharply dropped to 0.14 +/- 0.11/sec in the five Day 1 rats and gradually increased to 0.45 +/- 0.11/sec in the five Day 3 rats. Histologic examination of these rats revealed ischemic changes restricted to CA1 neurons on Days 2 and 3. The paired-pulse experiment showed no significant difference between six control and six Day 2 rats in the inhibition of the second population spike with interstimulus intervals of less than 400 msec. At interstimulus intervals of greater than 500 msec there was facilitation of the second spike, which lasted 5 seconds in Day 2 rats. This facilitation was not observed in control rats. Because CA3 neurons constitute the main input to CA1 pyramidal cells, decreased activity of CA3 neurons indicates less excitatory input to CA1 neurons.(ABSTRACT TRUNCATED AT 250 WORDS)     

大鼠全脑缺血再灌注损伤后海马白噬相关蛋白LC3表达变化的研究

目的研究自噬微管相关蛋白轻链3（microtubule—associated protein 1 light chain3,LC3）在大鼠全脑缺血损伤后海马的表达情况,并探讨自噬在脑缺血损伤中的意义。方法使用四动脉结扎法制作大鼠全脑缺血模型再灌注损伤模型,实验动物随机分为：假手术组（sham组）、缺血再灌注纽。在全脑缺血15min后,分别再灌注0,30min,3,6,12,24h,1,3d,使用Westernblotting的方法检测各个时间点大鼠全脑缺血／复灌后海马LC3Ⅱ／LC3 Ⅰ蛋白的表达情况来研究脑缺血再灌注损伤后海马自噬现象的变化情况。结果与假手术组相比,大鼠全脑缺血再灌注损伤后3h,海马区LC3Ⅱ／LC3Ⅰ蛋白的表达开始上调,在全脑缺血再灌注损伤后1d表达最强（P〈0．05）。结论大鼠全脑缺血再灌注损伤后海马LC3Ⅱ／LC3Ⅰ蛋白表达上调,表明脑缺血再灌注损伤后海马区域的自噬活性上调。     

Characterization of a recovery global cerebral ischemia model in the mouse.

Transgenic/knockout murine variants allow roles of specific proteins to be studied in cerebral ischemia. Because of the size of mice, however, study of prolonged recovery from global ischemia has been limited. This project characterized an adaptation of the rat two-vessel occlusion model of global ischemia for use in the mouse. C57B1/6J mice (8 weeks old; 21 +/- 1 g) were overnight fasted, anesthetized with halothane, intubated and mechanically ventilated. The right internal jugular vein and femoral artery were cannulated. Pericranial temperature was held at 37.0 degrees C. The carotid arteries were occluded and mean arterial pressure was reduced to 35 mmHg with 0.3 mg intra-arterial trimethaphan and venous exsanguination. Electroencephalographic isoelectricity was confirmed in cohort mice. Ten minutes later ischemia was reversed. Mice were allowed 1, 3 or 5 days survival followed by histologic analysis. Regional cerebral blood flow (CBF) was determined autoradiographically. Outcome effects of intra-ischemic hyperglycemia (approximately 350 mg/dl) or hypothermia (34 degrees C) were also examined. The mortality rate was less than 10% in all recovery groups. Ischemia caused reduction of CBF to < 2% of sham values in cortex, hippocampus, and caudoputamen. CBF was unchanged in thalamus, brainstem and cerebellum. CA1 damage, greater after 3 days vs. 1 day reperfusion, was not further increased at 5 days. Histologic injury was increased by hyperglycemia although seizures did not occur. Hypothermia reduced CA1 damage. This study demonstrates feasibility of using the two-vessel occlusion + hypotension recovery model in the mouse. Recovery intervals of > or = 3 days are required to account for delayed CA1 neuronal necrosis. Histologic outcome can be modulated by known physiologic determinants of ischemic brain damage.     

小檗碱对大鼠脑缺血后MCP-1表达的影响

目的探讨小檗碱处理对大鼠脑缺血后单核细胞趋化蛋白-1（MCP-1）表达的影响及小檗碱对脑缺血的神经保护作用。方法建立大鼠短暂性全脑缺血模型，采用尼氏体亚甲蓝染色观察脑缺血后大鼠脑海马CA1区神经元存活情况；采用免疫荧光染色方法检测脑缺血后大鼠缺血脑组织中MCP-1的表达情况。结果（1）与假手术组比较，脑缺血组大鼠脑海马CA1区神经元明显缺失，而小檗碱处理组大鼠脑海马CA1区神经元存活数明显多于缺血对照组；（2）与假手术组比较，脑缺血组大鼠脑缺血区MCP-1表达显著增多，而小檗碱处理显著降低了大鼠脑缺血区MCP-1的阳性表达。结论脑缺血引起MCP-1表达上调，提示MCP-1可能参与脑缺血损伤。小檗碱可抑制缺血脑组织MCP-1的表达，推测其可能经此途径减轻脑缺血的炎症反应而发挥一定的神经保护作用。     

The development of a new mouse model of global ischemia: focus on the relationships between ischemia duration, anesthesia, cerebral vasculature, and neuronal injury following global ischemia in mice

A new model for mouse global ischemia is presented, and the relationship of ischemia duration, cerebral vasculature, and ischemic neuronal injury has been determined. CD-1 mice anesthetized by chloral hydrate were subjected to global ischemia by bilateral common carotid artery occlusion under controlled ventilation for 3, 5, and 10 min. After evaluating the patency of the posterior communicating artery (PcomA) as hypoplastic or normoplastic, neuronal injury was independently determined in the striatum, cortex, and hippocampus in each hemisphere. Ischemic injury was strongly correlated with not only ischemia duration, but also with the patency of the PcomAs. Furthermore, neuronal injury developed in a delayed fashion after 3-min ischemia, while it was maximized at 24 h after 10-min ischemia. Physiological studies showed the induction of slight hypotension as compared with inhalation anesthesia, and improvement of blood gas data relative to spontaneous respiration. These data demonstrate the usefulness of this method to induce selective vulnerability and delayed neuronal cell death in mice, and to provide a useful model to study the detailed mechanism of global ischemia using transgenic or knockout mutant mice.     

Effect of hyperglycemia on neuronal changes in a rabbit model of focal cerebral ischemia

In clinical medicine, cerebral ischemia is frequently due to a focal, rather than global, insult. The effect of hyperglycemia in focal cerebral ischemia is not well defined. We studied the effect of hyperglycemia on neuropathologic changes in a rabbit model of focal cerebral ischemia. Rabbits were randomized to receive saline (n = 12) or glucose (n = 12) infusions. The left anterior cerebral and left internal carotid arteries were clipped after the infusion began. After 6 hours of occlusion, the area of severe ischemic neuronal damage in the left neocortex and striatum on two standard sections of brain was calculated and expressed as a percentage of the total area of the left cortex or striatum. The mean +/- SEM cortical area of severe ischemic neuronal damage was 22.1 +/- 2.8% in the glucose-treated rabbits and 34.0 +/- 4.6% in the saline-treated rabbits (p less than 0.05). The cortical area of severe ischemic neuronal damage was inversely correlated with plasma glucose concentration at the time of arterial clipping (p less than 0.05). We conclude that hyperglycemia is associated with decreased histologic neuronal injury in this model of focal cerebral ischemia and may be protective when cerebral ischemia occurs from a focal insult.     

尾静脉注射骨髓基质细胞和腹腔注射粒细胞集落刺激因子治疗大鼠脑梗死*☆

背景：骨髓间充质干细胞具有成神经分化特性,有很多试验也证实粒细胞集落刺激因子可以用于改善脑梗死后的神经功能。 目的：比较静脉移植骨髓间充质干细胞和腹腔注射粒细胞集落刺激因子动员干细胞来治疗大脑中动脉闭塞模型大鼠疗效。 方法：实验以改良的Zea-longa线栓法阻断大脑中动脉建立SD大鼠脑梗死模型,造模24 h后分别通过尾静脉注射骨髓间充质干细胞或腹腔注射粒细胞集落刺激因子。 结果与结论：两种治疗方法均可改善脑梗死模型大鼠的运动和认知功能,且粒细胞集落刺激因子对脑梗死模型大鼠的运动和认知功能的改善比尾静脉注射骨髓间充质干细胞明显,移植后第7,14天,粒细胞集落刺激因子组梗死面积小于骨髓间充质干细胞组(P < 0.05),粒细胞集落刺激因子组BrdU阳性细胞数多于骨髓间充质干细胞组(P < 0.05)。提示粒细胞集落刺激因子动员骨髓干细胞治疗脑梗死的疗效可能优于骨髓间充质干细胞静脉注射的移植方法。     

三磷酸胞苷二钠对脑缺血大鼠海马CA3区突触体素表达的影响

目的　研究局灶性脑缺血后海马 CA3 区突触体素的动态表达及其三磷酸胞苷二钠对其干预的影响。方法　选取 SD大鼠 60只 ,随机分为脑缺血后自然恢复组、药物干预组和假手术对照组。采用线栓法建立大脑中动脉脑缺血大鼠模型 ,应用免疫组化技术观察海马 CA3 区突触体素的表达。结果　脑缺血后自然恢复组大鼠突触体素的表达较对照组明显降低 (P<0 .0 1) ;但 7～ 2 1d突触体素的表达逐渐上调 (P<0 .0 1)。应用三磷酸胞苷二钠干预后 ,突触体素表达与自然恢复组相比明显升高。结论　脑缺血损伤后海马 CA3 区突触体素表达减少 ,但机体自身存在着神经元的修复和再生 ;三磷酸胞苷二钠可上调突触体素的表达 ,具有促进缺血神经元的修复、再生及突触重塑作用。     

苯甲酸雌二醇对慢性脑缺血大鼠海马胆碱乙酰转移酶变化及雌激素的影响

目的观察苯甲酸雌二醇对慢性脑缺血大鼠海马神经元胆碱乙酰转移酶的影响,以探讨胆碱乙酰转移酶的变化在慢性脑缺血发病中的作用及雌二醇对此变化的影响。方法采用双侧颈总动脉永久性结扎制备慢性脑缺血模型,30只大鼠随机分为假手术组、缺血组和雌二醇治疗组。各组于造模60d后,应用Y迷宫观察其行为学改变,采用免疫组化观测大鼠海马神经元胆碱乙酰转移酶的变化。结果治疗组较缺血组认知障碍明显改善（P〈0.01）,其海马胆碱乙酰转移酶的表达也明显增高（P〈0.01）。结论苯甲酸雌二醇能改善慢性脑缺血大鼠的认知功能可能与其提高海马区胆碱乙酰转移酶水平有关。     

Glucose-associated alterations in ischemic brain metabolism of neonatal piglets.

BACKGROUND AND PURPOSE: During global brain ischemia or hypoxia-ischemia in adults, hyperglycemia is deleterious to the brain. In contrast, similar adverse effects have not been found in neonatal animals. This investigation examined neonatal piglets to determine if there were specific alterations of ischemic brain metabolism associated with different systemic glucose concentrations and to potentially clarify the effects of hyperglycemia during ischemia in neonates. METHODS: Two groups of animals (n = 12 in each group) were studied during partial ischemia to compare the effects of hyperglycemia (plasma glucose concentration, 258 +/- 97 mg% [mean +/- SD]) with modest hypoglycemia (plasma glucose concentration, 62 +/- 23 mg%). A broad spectrum of cerebral blood flow reduction was achieved by combining inflation of a cervical pressure cuff with varying degrees of hemorrhagic hypotension. High-energy phosphorylated metabolites, intracellular pH, and cerebral blood flow were simultaneously measured using a magnetic resonance spectroscopic technique. Brain metabolic variables (beta-ATP, inorganic phosphorus, phosphocreatine, intracellular pH) were plotted as a function of blood flow reduction during partial ischemia for each group. RESULTS: During ischemia values of cerebral blood flow were comparably distributed between groups and ranged from 15% to 110% of those of control. At a given reduction of cerebral blood flow, hyperglycemic piglets maintained a higher concentration of beta-ATP (p = 0.011) and had a smaller increase in inorganic phosphorus (p less than 0.001). At cerebral blood flow less than 50% of control, the intracellular pH of piglets with modest hypoglycemia during partial ischemia was never reduced to less than 6.46, whereas intracellular pH fell as low as 5.97 for hyperglycemic animals. CONCLUSIONS: ATP preservation may account for the differing effects of glucose during ischemia in neonates compared with adults, provided that the accentuated brain acidosis is not deleterious to neonatal brain tissue.     

一种C-Jun N-末端激酶肽抑制剂在沙土鼠全脑缺血中的保护作用

目的 为了进一步研究海马C1区域神经细胞活动中JNK的作用，我们评价了一种JNK抑制剂即D-JNKI1在沙土鼠一过性大脑缺血模型中对迟发性神经细胞死亡（DND）的作用。方法 55只沙土鼠随机分为11个组。5组沙土鼠先接受5min前脑缺血处理，再灌注3h后，通过立体定向方法。向每组沙土鼠右侧侧脑室内分别注入不同浓度的D-JNKI1（2μL PBS内加入0．00012，0．0012，0．012，0．12，1．2μmol／L D-JNKI1，每组n=5）。对照组（n=5）：沙土鼠先接受5min前脑缺血处理，再灌注3h后，通过立体定向方法方法向右侧侧脑室内仅注入PBS2μL。腹腔内注射组（n=5）沙土鼠；先接受5min前脑缺血处理，再灌注3h后，1．2μmol／L D-JNKI1溶于0．5mL PBS腹腔内注射。假手术组（n=5）；沙土鼠仅暴露双侧颈总动脉，未夹闭。预处理组（共3组，n=15）：先将0．0012μmol／L D-JNKI1，0．00012μmol／L D-JNKI1溶于2μL PBS，分别注入两组沙土鼠的右侧侧脑室内，另外一组沙土鼠的右侧侧脑室内仅仅注入PBS2μL，30min后三组均夹闭双侧颈总动脉2min，48h后再次接受双侧颈总动脉夹闭5min。所有沙土鼠从接受夹闭5min双侧颈总动脉后4d处死，作冰冻切片和Niss1染色。结果 缺血再灌注3h后用D-JNKI-1治疗，有神经保护作用，最好的神经保护效应浓度为0．0012μmol／L。D-JNKI-1预处理加强了2min预处理所诱导的缺血耐受效应。结论D-JNKI1在沙土鼠全脑缺血模型中对海马CA1区域的迟发性神经细胞死亡有潜在的神经保护作用。     

大鼠全脑缺血再灌注损伤后海马自噬相关蛋白Beclin 1的表达变化

目的研究自噬相关蛋白Beclin 1在大鼠全脑缺血-再灌注损伤后海马中的表达情况,并探讨其意义。方法使用四动脉结扎法制作大鼠全脑缺血-再灌注损伤模型,实验动物随机分为：假于术组和缺血再灌注组。存全脑缺血15min后,分别再灌注0min、30min、3h、6h、12h、24h、1d、3d,使用Western blot检测各个时阃点大鼠全脑缺血-再灌后海马自噬相关蛋白Beclin1的表达情况。结果与假手术组比较,大鼠全脑缺血-再灌注损伤后1d,海马区Beclinl蛋白的表达最强（P〈0．05）。结论大鼠全脑缺血-再灌注损伤后海马自噬相关蛋白Beclinl表达上调,表明脑缺血-再灌注损伤后海马区域的自噬活性上调．     

Validation of a four-vessel occlusion model for transient global cerebral ischemia in dogs

A new model of transient global cerebral ischemia in dogs with minimal measures of intervention is described together with a simple scale for evaluation of functional outcome. During pentobarbital anesthesia, a global cerebral ischemia lasting seven minutes was induced by a four-vessel occlusion and a controlled systemic hypotension. The reperfusion phase begun after removal of arterial clamps, and the animals were sacrificed by perfusion fixation 24 hours latter. The efficiency of controlled systemic hypotension in diminishing collateral blood flow was validated in two experimental groups with different cerebral filling pressure (CFP). Severe ischemia group (CFP 1.0-1.5 kPa) underwent near-complete ischemia as indicated by rCBF, electroencephalography, and histologically documented ischemic neuronal changes. Mild ischemia group (CFP 2.5-3 kPa) animals experienced reduction in cerebral blood flow well above the ischemic threshold, had better functional outcome as well as no ischemic neuronal changes on light microscopy. This model consistently produces global cerebral ischemia in dogs with minimal surgical intervention and pharmacological support, and without intracranial hypertension, cardiac arrest or asphyxia. We recommend this model for outcome-oriented studies of complete forebrain ischemia in dogs.     

亚硒酸钠对脑缺血再灌注损伤大鼠HIF-1α表达的影响

目的 研究亚硒酸钠对大鼠脑缺血再灌注损伤后海马神经细胞凋亡的保护作用及其对低氧诱导因子-1α(HIF-1α)表达的影响.方法 48只SD大鼠随机分为假手术组、缺血再灌注组(模型组)及亚硒酸钠治疗组,每组16只,采用线栓法建立脑缺血再灌注模型,治疗组于再灌注后给予亚硒酸钠0.625 mg/(kg·d)腹腔注射7 d.各组大鼠经组织处理后用亚甲兰尼氏体染色及TUNEL染色,分别观察大鼠海马CA1区神经元存活和凋亡情况,Western Blot实验测定缺血组织HIF-1α水平的表达.结果 脑缺血再灌注损伤大鼠海马神经元数目明显减少,凋亡细胞明显增加(P<0.001),亚硒酸钠治疗后海马神经细胞存活数目明显增多,凋亡细胞明显减少(P<0.01);与假手术组比较,模型组大鼠海马HIF-1α水平表达明显增加(P<0.01),而经亚硒酸钠治疗后大鼠海马HIF-1α水平表达较模型组明显降低(P＜0.05).结论 亚硒酸钠可减轻脑缺血再灌注损伤大鼠神经元凋亡,同时能抑制组织HIF-1α的过度表达.