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1.
目的:观察并定量分析大鼠海马的微血管构筑及衰老变化。方法:采用单宁酸-氯化铁媒染微血管的方法分别观察青龄、老龄大鼠海马与额叶皮质的微血管构筑,并采用MiVnt图像分析系统对海马与额叶皮质的微血管密度(MVD)及微血管面积密度(MVA)进行定量分析。结果:老龄大鼠海马、皮质的微血管数量显著减少,分布杂乱、扭曲缠结。定量分析显示老龄大鼠海马、皮质的MVD值和MVA值均明显低于青龄大鼠,差异具有统计学意义。结论:老龄大鼠海马及额叶皮质的MVD值、MVA值均明显低于青龄大鼠,这是老年血管性痴呆发生机制的主要形态学依据。  相似文献   

2.
目的:观察大鼠脑缺血再灌注损伤后皮质微血管的变化,探讨丁苯酞对其作用。方法:线栓法制备大鼠脑缺血再灌注模型;单宁酸-氯化铁媒染法显示大脑皮质微血管,Mivnt图像分析系统定量分析微血管密度(MVD)和微血管面积密度(MVA);十湿重法检测脑含水量,透射电镜观察血脑屏障超微结构。结果:与假手术组相比,缺血再灌注组大鼠皮质微血管绝大部分闭合或僵直,MVD和MVA显著下降,脑含水量明显升高,电镜观察微血管腔狭窄,内皮细胞核固缩。丁苯酞组微血管形态好转,MVD和MVA升高,脑水肿和血脑屏障损伤程度均减轻。结论:丁苯酞可改善大鼠脑皮质微血管形态,减轻脑水肿和血脑屏障损伤,对脑缺血再灌注损伤有一定的预防性保护作用。  相似文献   

3.
目的:探讨雌激素对慢性脑缺血大鼠海马微血管构筑的影响.方法:采用永久性结扎去势大鼠双侧颈总动脉的方法建立慢性脑缺血模型,项背部皮下注射雌激素.单宁酸-氯化铁媒染法观察大鼠海马微血管构筑的动态变化,采用MiVnt图像分析系统对大鼠海马水平部的微血管密度(MVD)和微血管面积密度(MVA)进行定量分析.结果:模型组大鼠各时间点海马的MVA、MVD值均较正常对照组大鼠明显降低,且随着时间的延长,MVA、MVD值逐渐下降.雌激素治疗组大鼠各时间点海马的MVA、MVD值高于模型组同时间点,且随着用药时间的延长MVA、MVD逐渐上升.结论:雌激素可改善慢性脑缺血大鼠海马的微血管构筑,降低缺血、缺氧对于海马神经元的损伤.  相似文献   

4.
目的:探讨肝癌组织中微血管密度(microvascular density,MVD)、微血管面积(microvascular area,MVA)以及Piezo1的表达水平预测肝癌微血管侵犯(microvascular invasion,MVI)的临床价值.方法:应用免疫组织化学方法检测38例病理证实为肝癌患者的肝癌组织的CD34以及Piezo1的表达情况,计算基于CD34染色的MVD和MVA,分析MVI与MVD,MVA以及Piezo1因子的表达水平的相关性.结果:38例肝癌中,13例有微血管侵犯,定义MVI(+)组,25例无微血管侵犯,定义MVI(?)组.MVI(+)组的MVA及MVD均高于MVI(?)组,两组间差异有统计学意义(P=0.007,P=0.011).MVD和MVA联合预测MVI的敏感性和特异性为100%和64%,较单一指标效能高.Piezo1在肝癌MVI(+)组阳性率高于MVI(?)组,两组间差异有统计学意义(P=0.032).结论:MVD,MVA以及Piezo1的表达水平均与肝癌MVI具有一定的相关性,可以作为辅助诊断微血管侵犯的指标,Piezo1可以作为潜在的限制MVI的治疗靶点.  相似文献   

5.
成人海马结构微血管密度的形态计量学研究   总被引:5,自引:0,他引:5  
王有伟  宫瑾 《解剖学报》1995,26(3):235-239
用碱性磷酸酶血管染色法对成人海马结构内微血管密度进行了形态计量学研究。结果表明,海马皮质各层的微血管密度,以分子层最高,以下依次为锥体细胞层和多形细胞层,而腔隙层最低。海马皮质各区和齿状回的微血管密度,以CA2区最高,CA3和CA1区居中,CA4区次之,齿状回最低。微血管直径以海马锥体细胞层最大(8.20±2.1μm),多形细胞层最小(7.12±0.9μm)。CA2区的微血管直径最大(7.59±1  相似文献   

6.
目的:探讨黄芩茎叶总黄酮(SSTF)预处理对脑局灶性缺血再灌注大脑皮质的保护作用及其机制.方法:线栓法制备局灶性脑缺血再灌注模型,造模成功后24 h测脑梗死体积,单宁酸-氯化铁媒染法显示大脑皮质微血管,并用Mivnt图像分析系统对皮质微血管密度(MVD)及微血管面积密度(MVA)进行定量分析;检测脑皮质组织中超氧化物歧化酶(SOD)活力、丙二醛(MDA)含量.结果:SSTF预处理可改善术后大鼠的MVD和MVA;降低因缺血再灌注引起的脑皮质组织MDA含量增加,提高SOD活力.结论:SSTF预处理可改善脑皮质微血管形态结构,抵制脂质化过氧化反应,减轻自由基损害,对缺血再灌注损伤脑组织具有保护作用.  相似文献   

7.
目的定量研究兔蛛网膜下腔出血(SAH)后海马CA 1 区微血管形态学变化及相应的神经元病理改变 ,并观察尼莫通 (ND)的治疗作用。方法采用枕大池两次注血法制作兔SAH模型 ,运用内源性过氧化物酶法显示兔SAH后5d海马CA 1 区微血管 ,用体视学方法对脑微血管进行定量分析 ,并观察了海马CA1 区组织病理学变化。结果SAH后海马CA 1 区微血管除直径外 ,体积密度、长度密度、表面积密度较正常组均有明显下降 (P<0 .01) ,且存在神经元的变性坏死 ;ND治疗后海马CA 1 区微血管密度恢复正常 ,与SAH组比较有显著性差异 ,神经元数量显著增加 (P<0.01)。结论SAH后微循环障碍是继发性脑损伤的病理学基础 ;ND具有改善微循环 ,保护神经元的作用。  相似文献   

8.
目的:探讨葛根素(Pue)对缺血再灌注(IR)大鼠大脑皮质微血管和血脑屏障预防性保护作用。方法:SD大鼠随机分为假手术组(Sham组)、IR组、葛根素组和尼莫地平组(NIM组);葛根素组、NIM组分别于术前给予葛根素50 mg·kg~(-1)·d~(-1)、NIM 1mg·kg~(-1)·d~(-1)预处理,制备大脑中动脉阻塞脑缺血再灌注模型;单宁酸-氯化铁法(TA-Fe法)显示大脑皮质微血管,图像定量分析微血管密度(MVD)和微血管面积比(MVA);伊文思蓝(EB)和干湿重法检测脑组织含水量和血脑屏障(BBB)通透性,透射电镜观察大脑皮质BBB的超微结构变化。结果:与IR组相比,葛根素组脑组织含水量和微血管通透性明显降低,MVD、MVA显著增高,葛根素组与尼莫地平组差异无统计学意义。葛根素组、尼莫地平组的大脑皮质缺血区BBB超微结构变化接近,都表现为内皮细胞肿胀减轻,紧密连接趋于正常,基膜松散但连续,胶质膜排列较致密。结论:葛根素预处理可通过减轻微血管损伤、增加再通数量,降低血脑屏障的通透性,减轻脑水肿,预防性保护缺血再灌注损伤脑组织。  相似文献   

9.
目的 定量研究兔蛛网膜下腔出血(SAH)后海马CA1区微血管形态学变化及相应的神经元病理改变,并观察尼莫通(ND)的治疗作用。方法 采用枕大池两次注血法制作兔SAH模型,运用内源性过氧化物酶法显示兔SAH后5d海马CA1区微血管,用体视学方法对脑微血管进行定量分析,并观察了海马CA1区组织病理学变化。结果 SAH后海马CA1区微血管除直径外,体积密度、长度密度、表面积密度较正常组均有明显下降(P<0.01),且存在神经元的变性坏死;ND治疗后海马CA1区微血管密度恢复正常,与SAH组比较有显著性差异,神经元数量显著增加(P<0.01)。结论 SAH后微循环障碍是继发性脑损伤的病理学基础;ND具有改善微循环,保护神经元的作用。  相似文献   

10.
乳腺癌MMP-2表达与间质微血管密度和肿瘤转移的关系   总被引:7,自引:3,他引:7  
目的 :研究乳腺癌组织中基质金属蛋白酶 2 (MMP 2 )的表达特点 ,探讨其与间质微血管密度及肿瘤转移的关系。方法 :应用免疫组化S P法 ,检测 49例乳腺癌、10例癌旁正常组织MMP 2的表达 ,并在CD34染色切片上检测间质微血管密度(MVD)。结果 :乳腺癌组织MMP 2的表达 (75 5 % )明显高于癌旁正常组织 (30 % ) ,二者之间差异有显著性 (P <0 0 1) ;MMP 2阳性组MVD均值 (5 4 93± 13 86 )高于MMP 2阴性组 (4 1 2 8± 11 6 9) ,MMP 2的表达与MVD呈正相关 (P <0 0 1)。此外 ,乳腺癌MMP 2的表达与组织学分级、淋巴结转移密切相关 (P <0 0 5 ) ,而与患者年龄、肿瘤大小、组织学分型、临床分期无关。结论 :MMP 2促进乳腺癌间质血管生成 ,促进肿瘤的侵袭和转移 ,有可能成为判定乳腺癌生物学行为和预后的重要指标  相似文献   

11.
目的 探讨黄芩茎叶总黄酮(SSTF)对脑缺血再灌注海马区微血管、血脑屏障(BBB)损伤的预防性保护作用。 方法 SD大鼠90只,随机分为假手术组(sham组)、模型组(IR组)和SSTF预处理组,造模前1周SSTF各组灌胃给药,低、中、高剂量组分别给50、100、200 mg/(kg·d),共7d。IR组和SSTF各组制作脑缺血再灌注模型,术后评价神经功能缺损变化,干湿重法和伊文思蓝法检测脑组织含水量和微血管通透性,单宁酸 氯化铁媒染(TA-Fe)法显示并观测大鼠微血管密度(MVD)和微血管面积比(MVA),Real-time PCR法检测水通道蛋白4(AQP4) mRNA的表达水平,电镜观察血脑屏障完整性。 结果 SSTF各组与IR组比,神经功能缺损评分、脑组织含水量、微血管通透性明显降低(P<0.01,P<0.05),MVD、MVA增加(P<0.01), AQP4 mRNA表达增强(P<0.01),BBB损伤不同程度减轻,内皮细胞肿胀渐消退,紧密连接松解好转,基膜渐连续、清晰,胶质细胞足板胞质溶解减轻,渐接近正常;SSTF 中、高组上述表现较SSTF 低组好转的更明显(P<0.01),SSTF 中组与SSTF 高组比较差异无统计学意义(P>0.05)。 结论 SSTF干预对海马区微血管、血脑屏障和神经损伤有预防性保护作用,其作用机制可能是通过增加有效微血管再通数量,维持血脑屏障完整和功能,减轻脑水肿实现的。SSTF的有效预防剂量为100mg/(kg·d)。  相似文献   

12.
In brain, a major factor regulating local perfusion is local neuronal activity. However, we have recently discovered that, in rat, five days after selective neuronal destruction in the parietal cortex by local microinjections of the excitotoxin ibotenic acid, local cerebral blood flow, within the lesion, remains in the normal range. We studied whether proliferating non-neuronal cells and/or local changes in microvascular density participate to maintain local cerebral blood flow. Rats were anesthetized (halothane 1-3%), ibotenic acid (10 micrograms in 1 microliter) was locally microinjected in a restricted region of the parietal cortex, and animals were allowed to recover. Three, five, seven, 11, 30 days later local cerebral blood flow was measured autoradiographically under chloralose anesthesia (40 mg/kg, s.c.) by the [14C]iodoantipyrine technique. Cellular density or microvascular area were determined on sections stained with Thionine or processed for the endothelial marker alkaline phosphatase, respectively. Local neurons were destroyed by 24 h after microinjections of ibotenic acid. However, from three to 11 days after lesion local cerebral blood flow was unchanged (P greater than 0.05; n = 5), thereafter declining so that by 30 days blood flow was 48 +/- 6% of control (P less than 0.05; n = 5). Cellular density increased within the lesion by 17.5-fold at seven to 11 days (P less than 0.01) and declined to a 11.7-fold elevation above control at day 30 (P less than 0.01). New cells consisted of macrophages, endothelium and glial fibrillary acidic protein-positive astrocytes. The microvascular area increased 4.2-fold from three to 11 days (P less than 0.01). The patency of the presumably newly formed vessels was determined by the presence of intravascular red blood cells, which were revealed histochemically. The area occupied by red blood cells within cerebral microvessels, in contrast to microvascular area, did not increase until seven days after lesion, reaching a 3.2-fold increase at 11 days. Thus within the lesion, local cerebral blood flow remains constant during the phase in which cellular and microvascular density increases. The presumably newly formed vessels cannot contribute to maintain local cerebral blood flow since during this phase they are not patent; rather patency develops coincident with the decline in local cerebral blood flow. We conclude that non-neuronal cells, most likely activated macrophages, may be an important factor regulating local cerebral perfusion, after acute neuronal death.  相似文献   

13.
目的;研究正常大鼠大脑皮质额、顶、枕、颞叶的一氧化氮合酶(nitric oxide synthase,NOS)神经元及NOS阳性终末的分布,尤其注意它们与皮质微血管的关系。方法:采用NADPH-d组化方法。结果:NOS阳性神经元在皮质各层散在分布,数量较少,额、顶叶约半数的NOS神经元直接与皮质血管构成接触,枕、额叶中约三分之一的NOS神经元与皮质血管构成接触。而NOS阳性纤维多且密集成网状,额、顶叶的终末数量明显多于枕、颞叶,其中6%~7%的阳性终末分布至血管壁。结论:大脑皮质内的NOS神经元及NOS阳性终末参与皮质微循环的调节。  相似文献   

14.
This study describes the location and anatomical subdivisions of the auditory cortex of the horseshoe bat, Rhinolophus rouxi. The basic cyto- and myeloarchitectural features and cytochrome oxidase reactivity patterns are evaluated in brains where auditory fields have been previously established neurophysiologically (Radtke-Schuller and Schuller 1995). Thus, the neuroanatomical findings from these brains and additional analyzed material are related to neurophysiological characteristics. The neocortex of Rhinolophus shows a typical mammalian six-layered organization. It is poorly laminated, has a low density of granular elements, a wide layer I, and a phylogenetically old pyramidal cell type in a sharply accentuated layer II. These features are generally considered ’primitive’ or conservative. Frontal, parietal, temporal and occipital regions can be distinguished. In the temporal cortex, layers III and IV are found to be markedly thicker than layer V, in contrast to the parietal region, where a prominent layer V, containing a high concentration of large pyramidal cells is the most outstanding feature. The entire temporal region, most of the parietal and parts of the occipital region are responsive to auditory stimuli. The primary auditory field corresponds to most of the temporal region. The fields of the parietal region almost completely coincide with the dorsal fields of the auditory cortex. Border zones between the temporal, parietal, and occipital regions correspond to the posterior auditory field. The non-primary fields of the auditory cortex occupy a larger area of the bat’s neocortex than the primary field. The accentuated neuroarchitectural features, like cortical thickness and staining intensity, are shown to coincide with the physiological representation of biologically significant parameters. Accepted: 19 April 2001  相似文献   

15.
Microvessel density (MVD) has been reported to have prognostic relevance for clear cell renal cell carcinoma (ccRCC). However, this finding is controversial because of the difficulty of MVD evaluation in this complex vascularized tumor type. The present study evaluates the use of an automated quantitative analysis (AQUA) system for objective and reproducible determination of tumor vascularization in clear cell renal cell carcinoma (ccRCC). The AQUA system was applied to tissue microarrays with 284 primary ccRCC tumors. To determine angiogenesis in ccRCC, we created an epithelial/stromal mask consisting of CD10, epithelial membrane antigen, and vimentin to distinguish epithelial tumor cells from CD34-positive endothelial cells. Using immunofluorescence and computer-aided quantification of CD34 expression, we measured the relative microvessel area (MVA) and compared the MVA to the manually counted MVD. The MVA determined by AQUA in a test set with 209 ccRCCs ranged from 0% to 30.3% (mean +/- SD, 10.1% +/- 6.3%). The manually determined MVD ranged from 6 to 987 vessels/mm(2) (416.8 +/- 252.8 vessels/mm(2)). MVA and MVD were significantly correlated (P < .001). A larger MVA was associated with histologic grade (P < .001), tumor stage (P =.008), presence of metastasis (P = .005), presence of sarcomatoid areas (P < .001), and tumor-specific survival (P < .001). Using MVA as defined in the test set, all associations with clinical and pathologic parameters were confirmed in a second independent validation set. MVA determination by AQUA is an objective and reliable method to quantify tumor vascularization in ccRCC. A large MVA correlates with a high MVD and is associated with better patient prognosis.  相似文献   

16.
This study describes the location and anatomical subdivisions of the auditory cortex of the horseshoe bat, Rhinolophus rouxi. The basic cyto- and myeloarchitectural features and cytochrome oxidase reactivity patterns are evaluated in brains where auditory fields have been previously established neurophysiologically (Radtke-Schuller and Schuller 1995). Thus, the neuroanatomical findings from these brains and additional analyzed material are related to neurophysiological characteristics. The neocortex of Rhinolophus shows a typical mammalian six-layered organization. It is poorly laminated, has a low density of granular elements, a wide layer I, and a phylogenetically old pyramidal cell type in a sharply accentuated layer II. These features are generally considered ’primitive’ or conservative. Frontal, parietal, temporal and occipital regions can be distinguished. In the temporal cortex, layers III and IV are found to be markedly thicker than layer V, in contrast to the parietal region, where a prominent layer V, containing a high concentration of large pyramidal cells is the most outstanding feature. The entire temporal region, most of the parietal and parts of the occipital region are responsive to auditory stimuli. The primary auditory field corresponds to most of the temporal region. The fields of the parietal region almost completely coincide with the dorsal fields of the auditory cortex. Border zones between the temporal, parietal, and occipital regions correspond to the posterior auditory field. The non-primary fields of the auditory cortex occupy a larger area of the bat’s neocortex than the primary field. The accentuated neuroarchitectural features, like cortical thickness and staining intensity, are shown to coincide with the physiological representation of biologically significant parameters.  相似文献   

17.
Former studies have demonstrated the cortical regions being involved in visual motion processing. The strength of neuronal activation was found to depend on the direction of motion. In particular the detection of optic flow towards the observer seems of particular importance due to its obvious biological relevance. We used event related potentials (ERPs) to add data of the temporal dynamics of this neuronal processing. Using current density reconstruction, source maxima of differential activation in motion in depth versus planar motion in the time range from 50 to 400 ms after stimulus onset were localized, and the time courses of activation were elaborated. Source reconstruction revealed six regions contributing significant source activity related to the perception of motion in depth: occipital pole, bilateral fusiform gyrus, right lateral superior occipital cortex and bilateral superior parietal cortex. Our data provide evidence for an early involvement of visual occipital cortex in the perception of motion in depth stimuli, followed by activation within parietal cortex, presumably associated with attention information processing. Sub-dividing the effects of the direction of the stimuli in motion in depth perception, optic flow directed towards the observer-induced stronger activation, but this differential activation excluded the parietal cortex. Thus the temporal deconvolution of the electrophysiological data suggests that the differential processing of approaching stimuli is initiated at an early stage of visual perception within the visual association area.  相似文献   

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去卵巢大鼠骨密度变化与骨髓组织血管生成的关系   总被引:3,自引:1,他引:3       下载免费PDF全文
目的: 探讨去卵巢大鼠骨密度变化与骨髓组织血管生成的关系。方法:30只SD雌性大鼠随机分为去卵巢组(OVX)和假手术组(sham),分别在4周、8周和12周处死。取左侧股骨测量骨密度(BMD)。右侧远端股骨干骺端松质骨甲醛固定,EDTA-Na2脱钙。常规脱水、石蜡包埋、切片。行苏木素-伊红染色用于观察骨髓组织病理改变,用CD34标记血管内皮细胞观察微血管密度(MVD),采取大鼠腹主动脉血进行血管内皮生长因子(VEGF)测定。结果: 大鼠去卵巢8周后BMD明显低于假手术组, 提示骨质疏松模型建立,此时,骨髓造血组织容量减少,脂肪组织容量增高,与假手术组比较均有显著差异(P<0.01),骨髓组织MVD与假手术组比略有减少。12周后,上述改变更为明显。同时,骨小梁容量减少,骨髓组织MVD明显减少(P<0.05),且显示MVD与BMD、造血组织容量和骨小梁容量呈正相关,与脂肪组织容量呈负相关。但血浆VEGF含量测定OVX组与sham组间无明显差异,与骨髓组织各形态指标亦无相关性。结论:去卵巢大鼠在骨量丢失和造血组织容量减少的同时伴有骨髓组织MVD减少, 为骨质疏松症采用促微血管增生治疗提供了实验依据。  相似文献   

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