甲基强的松龙对兔实验性脑血管痉挛的作用

目的探讨大剂量甲基强的松龙对蛛网膜下腔出血（SAH）后脑血管痉挛（CVS）的作用。方法将24只雄性新西兰白兔随机分成2组：SAH对照组和SAH＋大剂量甲基强的松龙（MP，18mg／kg）治疗组。通过枕大池二次注血法构建SAH模型，观察MP对脑基底动脉的影响。应用酶联免疫生化技术检测各组兔基底动脉血管平滑肌细胞膜蛋白激酶C（PKC）活性。结果经脑血管造影证实该剂量甲基强的松龙明显减轻实验性脑血管痉挛的严重程度，与对照组相比，PKC活性在大剂量甲基强的松龙治疗组没有明显提高。结论大剂量甲基强的松龙能够明显减轻脑血管痉挛程度，通过抑制血管平滑肌细胞来防治脑血管痉挛的发生发展。     

腰穿枕大池置管2次注血的迟发性脑血管痉挛动物模型

目的 :制作一种操作简便、重复性好的蛛网膜下腔出血 (SAH)脑血管痉挛 (CV)动物模型。方法 :选取家猪 12头 ,随机分成SAH组和生理盐水对照组 ;SAH组经腰穿枕大池置管 2次注血 ,制成SAH模型 ,对照组注入生理盐水 ;以脑血管造影和基底动脉组织学改变判定脑血管痉挛。结果 :SAH组双侧颈内动脉和基底动脉明显痉挛 (P <0 0 1) ,基底动脉有典型病理改变 ,对照组未见异常。结论 :腰穿枕大池置管 2次注血法 ,是一种简便、可靠的SAH诱发CV动物模型制作方法。     

辛伐他汀对兔蛛网膜下腔出血后迟发性脑血管痉挛中血管壁增殖的影响

目的 探讨辛伐他汀对兔蛛网膜下腔出血(SAH)后迟发性脑血管痉挛(CVS)中血管壁增殖的影响.方法 36只新西兰大白兔随机分为3组:①对照组,常规饲养并枕大池二次注入0.9%生理盐水;②SAH组,通过二次枕大池注血建立SAH模型;③辛伐他汀+SAH组,每日胃灌辛伐他汀5 ms/kg,连续7 d后建立SAH模型.各组兔模型前后行两次脑血管造影.灌注后取基底动脉组织制作病理切片,分别于光镜和透射电镜下观察其显微以及超微结构.采用免疫组化及免疫荧光方法检测基底动脉组织中增殖细胞核抗原(PCNA)及α-平滑肌肌动蛋白(α-SMA)表达量的变化,同时采用Real-Time PCR检测其血小板源性生长因子-B(PDGF-B)基因表达量的变化.采用SPSS10.0软件进行统计分析.结果 通过脑血管造影可以观察到二次注血后兔基底动脉出现明显的痉挛,管径变细;而给予辛伐他汀后,痉挛减轻.SAH组兔基底动脉壁略有增厚,电镜显示平滑肌细胞内合成旺盛;而给予辛伐他汀预处理后这些变化明显减轻.SAH组兔基底动脉管壁平滑肌细胞内α-SMA、PCNA、PDGF-B表达明显高于对照组(P＜0.05),而给予辛伐他汀后三者表达量明显降低(P＜0.05).结论 辛伐他汀可能通过抑制迟发性CVS中血管壁平滑肌细胞的增殖来缓解SAH后迟发性CVS.     

SAH后迟发性脑血管痉挛中ICAM-1的表达变化及ICAM-1单克隆抗体和甲基强的松龙的防治作用

目的检测自发性蛛网膜下腔出血(SAH)后迟发性脑血管痉挛(DCVS)动脉中内皮细胞间粘附分子-1(ICAM-1)表达变化,同时评价ICAM-1单克隆抗体和甲基强的松龙的防治效果。方法中国白兔48只,体重2～2.5kg,随机分为四组。A组:正常对照组(n=8),不做枕大池穿刺注血,Day0处死;B组:SAH组(n=24),采用枕大池二次注血SAH模型,即在Day0和Day2第一、二次枕大池注血,并分别在Day4、Day7和Day14分三批处死,每批8只;C组:SAH+ICAM-1单克隆抗体和甲基强的松龙组(n=8),枕大池注射ICAM-1单克隆抗体10μg,耳缘静脉注射甲基强的松龙30mg/kg,并在Day7处死;D组:SAH+生理盐水组(n=8),用等量37℃生理盐水代替ICAM-1单克隆抗体和甲基强的松龙,第一次注血后Day7处死。结果A组动物基底动脉组织结构正常。B组动物基底动脉在Day4、Day7时出现血管痉挛,Day7时最严重,Day14时血管痉挛缓解。C组动物基底动脉痉挛明显缓解(P<0.05)。而D组动物基底动脉脑血管痉挛无缓解。B组动物基底动脉壁ICAM-1表达于day4开始增加,day7达到高峰,day14降至正常水平。C组ICAM-1表达明显减弱,与B组(day7)和D组比较有显著差异(P<0.01)。结论在兔SAH后迟发性脑血管痉挛中ICAM-1表达变化与DCVS炎症反应时相一致。应用ICAM-1单克隆抗体和甲基强的松龙,可抑制炎症反应的启动和进展,减轻炎症反应从而缓解DCVS。     

蛛网膜下腔出血后白细胞介素-8基因在兔脑基底动脉中表达的变化(英文)

目的探讨实验性蛛网膜下腔出血(SAH)诱发脑血管痉挛时,白细胞介素-8(IL-8)基因在兔脑基底动脉中表达的变化及在诱发脑血管痉挛中的作用。方法 35只健康日本大耳白兔随机分为生理盐水组、SAH组。SAH组根据第一次注血时间又分为四组,分别为第一次注血后第1、4、7、14 天。以枕大池二次注血法构建迟发性脑血管痉挛模型,采用RT-PCR法观察兔基底动脉中细胞因子IL-8 mRNA表达的变化。结果 IL-8mRNA在SAH组第一次注血后第4- 7天升高,14 天趋于正常。SAH组IL-8 的表达水平与基底动脉的狭窄程度呈正相关(r = 0.642,P < 0.01)。结论 IL-8在基底动脉中的表达水平与脑血管痉挛的程度紧密相关,提示IL-8可能作为免疫/炎症因素因素参与了SAH 后迟发性脑血管痉挛的发生。     

缝隙连接阻断剂1-庚醇对脑血管痉挛的抑制作用

目的探讨缝隙连接在脑血管痉挛中的作用及观察其阻断剂在动物实验中的治疗作用。方法建立兔二次蛛网膜下腔出血模型,通过脑血管造影观察经动脉或池内注入缝隙连接阻断剂heptanol,对脑血管痉挛的抑制和治疗作用,并观察基底动脉的形态学变化。结果枕大池注血后血管造影显示基底动脉出现痉挛。在脑血管痉挛后,动脉给予heptanol对急、慢性脑血管痉挛有显著的治疗作用。预先枕大池注入heptanol再注血,造影显示基底动脉痉挛不明显(P>0.05),heptanol枕大池预处理后能显著抑制急、慢性期脑血管痉挛的形成。形态学检查发现,对照组第7d的基底动脉光镜见内皮细胞核染色质聚集,内弹力膜波纹状,平滑肌细胞分布稀疏等。动脉给药组和池内给药组也有类似变化,但范围局限、程度轻。结论缝隙连接阻断剂heptanol能有效抑制兔蛛网膜下腔出血后急性和慢性脑血管痉挛,体内试验表明缝隙连接在脑血管痉挛中可能发挥重要作用,应用其阻断剂heptanol具有显著的治疗作用。     

Trapidil对蛛网膜下腔出血后脑血管痉挛作用的实验研究

目的 探讨蛛网膜下腔出血（SAH）后脑血管痉挛的发生机制及其可能的治疗方法。方法 利用家兔枕大池内注血构建SAH模型，观察血小板衍生生长因子（PDGF）拮抗剂trapidil对脑基底动脉的影响。结果 脑基底动脉于SAH后48h明显变细；静脉或动脉内持续灌注trapidil 15min（1．5mg／min）后，数字减影脑血管造影（DSA）显示痉挛血管已明显扩张变粗，30min时达高峰。结论 PDGF可能参与脑血管痉挛发生的病理过程，PDGF拮抗剂trapidil可有效缓解实验性SAH后脑血管痉挛，有望成为脑血管痉挛的治疗药物。     

蛛网膜下腔出血对兔脑基底动脉内皮细胞松弛因子释放及环-磷酸鸟苷含量的影响

本文观察蛛网膜下腔出血(SAH)对兔基底动脉内皮细胞松弛因子(EDRF)释放及环-磷酸鸟苷(cGMP)含量的影响。SAH 引起明显脑血管痉挛,同时明显降低了离体时乙酰胆硷(Ach)经过基底动脉诱发的生物检定环松弛,并降低了基底动脉 cGMP 含量。实验结果提示 SAH 可抑制基底动脉 EDRF 的释放及降低平滑肌胞浆中 cGMP 水平,从而降低基底动脉的松弛反应,易导致脑血管痉挛发生。     

粉防己碱对实验性脑血管痉挛核因子-κB活性变化的影响

目的探讨粉防己碱(Tet)对实验性脑血管痉挛动脉核因子-κB(NFκ-B)活化的影响以及对血管痉挛的防治作用。方法对日本大耳白家兔采用枕大池二次自体动脉血注入法制做蛛网膜下腔出血(SAH)模型。动物随机分为4组:对照组(n=10)、单纯注血组(n=10)、Tet干预组(n=10)和生理盐水干预组(n=10,动物给予等量生理盐水腹腔注射),于第一次注血后第7天将动物处死,取基底动脉进行形态学观察,应用免疫组化及电泳迁移率改变分析等方法检测NFκ-B活性表达变化。结果单纯注血组较对照组基底动脉出现明显管腔狭窄、炎性浸润等改变,NFκ-B的活性也明显增高;Tet干预组较单纯注血组痉挛程度和炎性浸润明显减轻,同时NFκ-B活性明显下降,而生理盐水组较单纯注血组则无明显差异。结论Tet能够通过直接抑制炎性细胞浸润和NFκ-B的激活从而显著减轻脑血管痉挛的程度和血管壁炎性浸润程度。     

甘珀酸对兔脑血管痉挛时缝隙连接蛋白43磷酸化表达的影响

目的 探讨甘珀酸对兔实验性蛛网膜下腔出血(SAH)后脑血管痉挛(CVS)时缝隙连接蛋白43(Cx43)磷酸化表达的影响.方法 建立兔二次SAH模型,脑池及静脉分别给予甘珀酸,脑血管造影及光镜观察分析基底动脉直径及形态学变化并应用Western blot检测基底动脉Cx43蛋白磷酸化表达的变化.结果 SAH组与正常组相比,脑血管造影及光镜观察结果 证实基底动脉痉挛明显;痉挛动脉肇磷酸化的Cx43(P-Cx43)蛋白表达显著升高,但去磷酸化的Cx43(NP-Cx43)蛋白表达显著减少.甘珀酸脑池处理组及静脉处理组与SAH组相比,脑血管造影及光镜观察结果 证实基底动脉痉挛显著减轻;痉挛动脉壁P-Cx43蛋白表达显著减少,但NP-Cx43蛋白表达显著升高.结论 SAH后,Cx43蛋白磷酸化表达发生变化,脑池或静脉给予甘珀酸能明显缓解SAH后CVS,其作用机制可能与基底动脉Cx43蛋白磷酸化表达变化有关.     

High-dose methylprednisolone and 'ex vivo' release of eicosanoids after experimental subarachnoid haemorrhage

In the present study we have investigated the effects of high-dose methylprednisolone (MP) treatment on the 'ex vivo' release of four major eicosanoids in an experimental model of subarachnoid haemorrhage (SAH) with the aim of verifying: (a) the efficacy in reducing arachidonic acid metabolism enhancement; (b) whether high-dose methylprednisolone is effective on both the cyclooxygenase and lipoxygenase pathways; and (c) discussing the possible role of high-dose MP treatment in brain protection after SAH. Levels of prostaglandin D2 and E2, prostacyclin and also leukotriene C4 were determined by the radioimmunoassay technique after 1 h incubation of cerebral cortex samples of rats which had been subjected to experimental SAH procedure (injection of 0.3 ml of autologous arterial blood). The release of prostaglandin D2 at 48 h after SAH is significantly higher when compared to that of sham-operated animals (P less than 0.01); prostaglandin E2 release is significantly enhanced at 6 h after the SAH procedure (P less than 0.01); release of the lipoxygenase metabolite is significantly enhanced at 1, 6 and 48 h after SAH induction; MP significantly decreases the release of all eicosanoids, and values in treated animals do not differ from those of sham-operated animals. The results of the present study suggest that the global inhibitory effect of high-dose MP treatment on the 'ex vivo' release of eicosanoids after experimental SAH could be considered to be one of the neurochemical correlates for the reduced incidence and severity of arterial inflammatory response, which results in chronic vasospasm and supports the clinical evidence of MP efficacy in preventing or reducing the incidence of arterial vasospasm after aneurysmal rupture.     

The effects of endothelin antagonist BQ-610 on cerebral vascular wall following experimental subarachnoid hemorrhage and cerebral vasospasm

Abstract. Endothelin, a potent vasoconstrictor, has been found to increase in the cerebrospinal fluid and serum of patients following subarachnoid hemorrhage (SAH) and to play a major role in the development of cerebral vasospasm. The aim of this study is to investigate the role of endothelin-A antagonist BQ-610 in the experimentally performed cerebral vasospasm following SAH. Thirty New Zealand rabbits were divided into three groups (each n = 10): group A, control group; Group B, SAH group; Group C, treatment (endothelin antagonist BQ-610 treated) group. In the study, the rabbits developed vasospasm after injection of intracisternal autolog blood into the cisterna magna. After cerebral vasospasm development, in group C, endothelin antagonist BQ-610 was injected intracisternally. Morphometrically, basilar artery lumen was constricted 25% and 62% compared to the control group (group A) in the endothelin treated group (group C) and the endothelin untreated group (group B), respectively. Histopathological findings of the basilar artery wall confirmed the therapeutic effect of endothelin antagonist in vasospasm development. Endothelin-A receptor antagonist BQ-610 has a therapeutic effect in the cerebral vasospasm following experimentally performed subarachnoid hemorrhage when used intracisternally.     

High-dose methylprednisolone and 'ex vivo' release of eicosanoids after experimental subarachnoid haemorrhage

In the present study we have investigated the effects of high-dose methylprednisolone (MP) treatment on the 'ex vivo' release of four major eicosanoids in an experimental model of subarachnoid haemorrhage (SAH) with the aim of verifying: (a) the efficacy in reducing arachidonic acid metabolism enhancement; (b) whether high-dose methylprednisolone is effective on both the cyclooxygenase and lipoxygenase pathways; and (c) discussing the possible role of high-dose MP treatment in brain protection a fter SAH. Levels of prostaglandin D2 and E2, prostacyclin and also leukdtriene C4 were determined by the radioimmunoassay technique after 1 h incubation of cerebral cortex samples of rats which had been subjected to experimental SAH procedure (injection of 0.3 ml of autologous arterial blood). The release of prostaglandin D2 at 48 h after SAH is significantly higher when compared to that of sham-operated animals (P < 0.01); prostaglandin E2 release is significantly enhanced at 6 h after the SAH procedure (P < 0.01); release of the lipoxygenase metabolite is significantly enhanced at 1, 6 and 48 h after SAH induction; MP significantly decreases the release of all eicosanoids, and values in treated animals do not differ from those of sham-operated animals. The results of the present study suggest that the global inhibitory effect of high-dose MP treatment on the 'ex vivo' release of eicosanoids after experimental SAH could be considered to be one of the neurochemical correlates for the reduced incidence and severity of arterial inflammatory response, which results in chronic vasospasm and supports the clinical evidence of MP efficacy in preventing or reducing the incidence of arterial vasospasm after aneurysmal rupture.     

Intracisternal administration of SB203580, a p38 mitogen-activated protein kinase inhibitor,attenuates cerebral vasospasm via inhibition of tumor-necrosis factor-α

Tumor-necrosis factor-α (TNF-α) is critical to the development of cerebral vasospasm after subarachnoid hemorrhage (SAH). Hence, therapeutic strategies targeting TNF-α can attenuate cerebral vasospasm. This study investigated the effects of SB203580, a p38 mitogen-activated protein kinase (MAPK) inhibitor, on TNF-α concentration in the cerebral arteries and the cerebrospinal fluid (CSF) after SAH and on subsequent cerebral vasospasm. Twenty-three rabbits were divided into four groups: (i) control (without SAH), (ii) SAH (SAH only), (iii) dimethylsulfoxide (DMSO, vehicle), and (iv) SB203580. The severity of vasospasm and the immunoreactivities of TNF-α and phosphorylated p38 MAPK in the brain vessels were determined in all animals, and the concentrations of TNF-α in the CSF were also assessed. Severe vasospasm was observed in the rabbits from the SAH and DMSO groups. SB203580 reversed vasospasm after SAH. Lower immunoreactivities of TNF-α and phosphorylated p38 MAPK were found in the basilar artery in the SB203580 group than in the DMSO group. The concentration of TNF-α in the CSF increased after SAH, but treatment with SB203080 after SAH suppressed this increase. Our data show that SB203580 reversed cerebral vasospasm by inhibiting the phosphorylation of p38 MAPK in the basilar artery and by suppressing the increase in TNF-α in the basilar artery and CSF after SAH. SB203580 could therefore potentially be used for the treatment of cerebral vasospasm after SAH.     

The effect of mexiletine on the level of lipid peroxidation and apoptosis of endothelium following experimental subarachnoid hemorrhage

OBJECTIVE: The role of apoptosis in etiopathogenesis of vasospasm is not clearly understood yet. It is widely accepted that protection of the endothelial cells from the process of apoptosis could have beneficial effects on cerebral vasospasm after subarachnoid hemorrhage (SAH). Mexiletine blocks sodium and calcium channels and activates ATP-sensitive K(+) channels. Moreover, mexiletine is known to have potent antioxidant effects through inhibiting free-radical production. METHODS: Twenty-one rabbits were allocated into three groups randomly. Group I was sham operated group (n=7). SAH occurred but no medication was given to the Group II rabbits (SAH only group) (n=7). Mexiletine (50 mg/kg, b.i.d., i.p.) was administered just before SAH and continued until 48 hours following SAH to the Group III rabbits (Mexiletine treated group) (n=7). The ApopTag peroxidase in situ apoptosis detection kit (Serologicals Corporation, former Intergen) was used to demonstrate apoptosis in a cross section of basillary arteries. Thiobarbituric acid reactive material was used to determine the lipid peroxidation levels. RESULTS: There was a statistically significant difference between lipid peroxidation product levels of the control and SAH only groups (p<0.05). The level of lipid peroxidation production in Mexiletine treated group was significantly lower compared with SAH only group (p<0.05) but not significantly higher than the control group (p>0.05). DISCUSSION: In the present study we investigated the antioxidant action of mexiletine on apoptosis of endothelium following a rabbit SAH model. This experimental study directly suggested that lipid peroxidation is an important step in development of apoptosis in endothelial cells and prevention of structural integrity of endothelial cell should play a beneficial role in attenuation of cerebral vasospasm. Mexiletine treatment prevented the increase in lipid peroxidation and cerebral vasospasm. Examination of endothelial cells by staining specific for apoptosis demonstrated significant protection of cell integrity in the treated group.     

High-dose methylprednisolone prevents vasospasm after subarachnoid hemorrhage through inhibition of protein kinase C activation

We have previously shown that the inflammatory process after subarachnoid hemorrhage causes vasospasm. The efficacy of methylprednisolone by suppression of the inflammatory process has been reported, although pharmacological mechanisms have not been clarified. The purpose of this study was to investigate the pharmacological mechanism of methylprednisolone on vasospasm. Using the 'two-hemorrhage' canine model, progression of angiographic vasospasm was assessed in nontreated and treated groups with methylprednisolone. Methylprednisolone 10 mg kg-1 was injected i.v. after the first injection of blood, and the same dose was injected every 12 h until day 7. Protein kinase C (PKC) activity of canine basilar arteries in both groups was measured during the course of vasospasm. In the isometric tension study, the effect of methylprednisolone on tensions induced by phorbol 12-myristate 13-acetate (PMA), or high-K+ solution, was also evaluated. Methylprednisolone significantly reduced severity of vasospasm. In the treated group, PKC activity was not enhanced compared with the nontreated group at any point. Methylprednisolone inhibited tonic tension induced by PMA, but not that induced by high-K+ solution. We conclude that methylprednisolone prevents severity of vasospasm through inhibition of PKC activation, but does not work as a Ca2+ channel blocker.     

Potential contribution of nuclear factor-kappaB to cerebral vasospasm after experimental subarachnoid hemorrhage in rabbits.

Nuclear factor-kappaB (NF-kappaB) plays a key role in inflammation, which is involved in the development of cerebral vasospasm after subarachnoid hemorrhage (SAH). In the present study, we assessed the potential role of NF-kappaB in regulation of cerebral vasospasm. Nuclear factor-kappaB DNA-binding activity was measured in cultured vascular smooth muscle cells (VSMCs) treated with hemolysate and pyrrolidine dithiocarbamate (PDTC, 80 micromol/L), an inhibitor of NF-kappaB. Forty-two rabbits were divided into three groups: control, SAH, and PDTC groups (n=14 for each group). The caliber of the basilar artery was evaluated. Nuclear factor-kappaB DNA-binding activity and the gene expression levels of cytokines and adhesion molecules in the basilar artery were measured. Immunohistochemical study was performed to assess the expression and localization of tumor necrosis factor (TNF)-alpha, intercellular adhesion molecule (ICAM)-1, and myeloperoxidase (MPO). It was observed that NF-kappaB DNA-binding activity was significantly increased by treatment with hemolysate in cultured VSCMs, but this increase was suppressed by pretreatment with PDTC. Severe vasospasm was observed in the SAH group, which was attenuated in the PDTC group. Subarachnoid hemorrhage could induce increases of NF-kappaB DNA-binding activity and the gene expression levels of TNF-alpha, interleukin (IL)-1 beta, ICAM-1, and vascular cell adhesion molecule (VCAM)-1, which were reduced in the PDTC group. Immunohistochemical study demonstrated that the expression levels of TNF-alpha, ICAM-1, and MPO were all increased in the SAH group, but these increases were attenuated in the PDTC group. Our results suggest that NF-kappaB is activated in the arterial wall after SAH, which potentially leads to vasospasm development through induction of inflammatory response.     

The effect of mexiletine on the level of lipid peroxidation and apoptosis of endothelium following experimental subarachnoid hemorrhage

Abstract

Objective: The role of apoptosis in etiopathogenesis of vasospasm is not clearly understood yet. It is widely accepted that protection of the endothelial cells from the process of apoptosis could have beneficial effects on cerebral vasospasm after subarachnoid hemorrhage (SAH). Mexiletine blocks sodium and calcium channels and activates ATP-sensitive K+ channels. Moreover, mexiletine is known to have potent antioxidant effects through inhibiting free-radical production.

Methods: Twenty-one rabbits were allocated into three groups randomly. Group I was sham operated group (n=7). SAH occurred but no medication was given to the Group II rabbits (SAH only group) (n=7). Mexiletine (50 mg/kg, b.i.d., i.p.) was administered just before SAH and continued until 48 hours following SAH to the Group III rabbits (Mexiletine treated group) (n=7). The ApopTag peroxidase in situ apoptosis detection kit (Serologicals Corporation, former Intergen) was used to demonstrate apoptosis in a cross section of basillary arteries. Thiobarbituric acid reactive material was used to determine the lipid peroxidation levels.

Results: There was a statistically significant difference between lipid peroxidation product levels of the control and SAH only groups (p<0.05). The level of lipid peroxidation production in Mexiletine treated group was significantly lower compared with SAH only group (p<0.05) but not significantly higher than the control group (p>0.05).

Discussion: In the present study we investigated the antioxidant action of mexiletine on apoptosis of endothelium following a rabbit SAH model. This experimental study directly suggested that lipid peroxidation is an important step in development of apoptosis in endothelial cells and prevention of structural integrity of endothelial cell should play a beneficial role in attenuation of cerebral vasospasm. Mexiletine treatment prevented the increase in lipid peroxidation and cerebral vasospasm. Examination of endothelial cells by staining specific for apoptosis demonstrated significant protection of cell integrity in the treated group.     

Comparison between one- and two-hemorrhage models of cerebral vasospasm in rabbits

Injection of blood into the cisterna magna is one of the most frequently used methods to produce subarachnoid hemorrhage (SAH) models in animals. Although the two-hemorrhage model of vasospasm is frequently used in canine and rat models, most studies with rabbits only use the one-hemorrhage model. In the present study, we accomplished a side-by-side comparison between one- and two-hemorrhage models in rabbits. A total of 38 rabbits were randomly divided into three groups, i.e. control group (n = 5), one (n = 15)- and two (n = 18)-hemorrhage model groups. The degree of cerebral vasospasm, the time course of cerebral vasospasm, the clinical behavior, and the residual amount of subarachnoid blood clots were measured on days 3, 5 and 7 after the establishment of the models. Compared with one-hemorrhage model, the time course of vasospasm in the two-hemorrhage model was more coincident with that observed in humans, produced more severe vasospasm after SAH, and had an acceptable low mortality. In conclusion, the two-hemorrhage model in rabbits is more appropriate than the one-hemorrhage model for the research on SAH or cerebral vasospasm, and thus can be used for the investigation of the mechanisms of and therapeutic approaches for cerebral vasospasm.     

氢化泼尼松对蛛网膜下腔出血患者脑灌注的影响

目的探讨大剂量氢化泼尼松对蛛网膜下腔出血(SAH)后脑血管痉挛(CVS)患者脑灌注的影响。方法将19例CT分级在Ⅲ级以下的SAH患者随机分成2组:①治疗组,大剂量氢化泼尼松(1.0mg/kg)冲击治疗。②对照组,单纯应用一般治疗。氢化泼尼松冲击治疗3天后,行脑CT灌注成像扫描,监测颞叶及额叶脑血管灌注情况,结合临床症状判断脑血管痉挛的程度。结果9例应用大剂量氢化泼尼松加上一般治疗的患者,与单纯一般治疗组相比,临床症状及额叶、颞叶的脑血流情况均得到明显改善。脑血容量(CBV),脑血流量(CBF),平均通过时间(MTT),较对照组有明显提高(P(0.05)。结论大剂量氢化泼尼松冲击治疗能够提高蛛网膜下腔出血患者的脑灌注,从而减轻脑血管痉挛,改善脑供血。