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1.
目的 研究凉血通瘀方对高血压大鼠急性脑出血模型脑组织miRNA表达的影响,对差异表达的miRNA靶基因进行分析,探索凉血通瘀方可能的药效机制。方法 将自发性高血压大鼠随机分成对照组(B)和实验组(C)。适应性饲养一周后,C组灌胃凉血通瘀方,B组灌胃等体积生理盐水,连续5天,每天1次。构建脑出血模型后收集脑组织,借助全转录组测序技术获得miRNA表达量,与miRBase数据库比对获取已知miRNA,使用miRDeep2预测新miRNA。差异分析软件为DESeq2,筛选阈值为|log2FC| ≥1 并且P <0.05。对显著差异表达的miRNA进行靶基因预测,对靶基因进行GO功能、KEGG通路富集和PPI网络分析。结果 实验组和对照组对比,共发现21个显著差异表达的miRNA,上调有9个,下调有12个,共预测得到1243个有统计学意义的靶基因。GO富集分析发现,生物过程中突触囊泡分泌的调节、神经递质分泌的调节和神经递质运输的调节占前三位,神经元投射终点、全膜、质膜区域和细胞投射则是主要的细胞成分。分子功能分别为小GTPase绑定、底物特异性跨膜转运蛋白活性和离子跨膜转运体活性。通路分析结果显示,靶基因在癌证通路、pI3K-Akt信号通路、人类乳头瘤病毒感染、神经活性配体-受体相互作用和MAPK通路等分布广泛。采用STRING网站和Cytoscape软件,根据MCC算法筛选出ADRA2C、CASR、CCL28、CCR1、DRD2、GNAT3、GRM2、DYNC1LI1、GABBR1、GNAI1等核心靶基因。结论 凉血通瘀方对脑出血急性期鼠脑组织内miRNA的表达有重要影响;显著差异表达miRNAs可能通过靶向核心基因调控凉血通瘀方干预急性脑出血的病理过程及预后。  相似文献   
2.
大鼠静脉窦高压致硬膜血管变化的研究   总被引:1,自引:1,他引:0  
目的探讨大鼠静脉窦高压后硬膜血管变化及其静脉窦高压在硬脑膜动静脉瘘形成中的作用。方法体重200~250g的SD雄性大鼠110只,随机分为静脉窦高压组(85只)和假手术组(25只),将静脉窦高压组85只大鼠闭塞左侧横窦和上矢状窦前1/3,并吻合右侧颈总动脉和颈外静脉,制成静脉窦高压模型。假手术组大鼠单纯解剖相应的颈部血管和硬脑膜窦,但不行吻合或闭塞。术后90d,随机取7只静脉窦高压组大鼠和5只假手术组大鼠,行硬脑膜血管明胶墨汁灌注,观察硬膜血管的状况。结果术后90d静脉窦高压组和假手术组大鼠的硬膜血管数分别为(10.7±1.5)条/mm,(10.3±0.6)条/mm,差异无显著性。在静脉窦高压组中1只大鼠有硬脑膜动静脉瘘,其形态和结构与生理性动静脉短路类似。结论大鼠静脉窦高压一段时间后,颅内硬膜血管无明显增生。颅内硬脑膜动静脉瘘的形成很可能是由动静脉间的短路发展而来。  相似文献   
3.
大鼠脑组织单胺类递质及其代谢产物的检测方法研究   总被引:13,自引:0,他引:13  
目的 :研究大鼠脑组织中单胺类递质及其代谢产物的高效液相反相离子对色谱测定法。方法 :采用LiChrosorbC18,10 μm色谱柱 ,流动相为甲醇 :水 (4 0 :60 ) ,含 0 .0 2 8g LEDTANa2 ,0 .15g LSDS ,0 .2ml LH2 SO4(pH 2 .5~ 3 ) ,荧光检测波长 :λEX=2 85 ,λEM=3 3 3。结果 :对 87只大鼠脑组织中 4种单胺类递质及其代谢产物的含量进行了同时测定 ,高香草酸 (HVA) 2 .5 0~ 40 .0 μg ml、去甲肾上腺素 (NE) 0 .0 1~ 0 .5 0 μg ml、多巴胺 (DA)0 .0 5~ 1.0 0 μg ml、5 羟色胺 (5 HT) 0 .0 2 5~ 0 .5 0 μg ml,峰面积与其含量呈良好的线性关系。 结论 :该法操作简便、快速、准确 ,为组织中单胺类递质及其代谢产物检测的一种理想方法 ,并适用于临床相关研究。  相似文献   
4.
用5只猫于左侧颈部食管壁内注入 HRP 溶液,通过 HRP 逆行追踪法研究颈部食管的交感神经支配,结果表明:1.长轴突型交感节前神经元直接分布到食管壁内,其标记细胞位于双侧脊髓的胸1~3节段,以胸2节段最多(占标记细胞总数的66.45%),注射侧占优势。标记细胞主要位于中间带外侧核(约占95.02%),其次为侧索、中介核、前角腹后外侧核。其细胞形态不一,以中小型细胞为主(占标记细胞总数的90.4%)。2.支配颈部食管的交感节后神经元主要位于星状神经节(约占61.99%),余者位于双侧颈前、中和2~5胸交感节内、以小细胞最多。  相似文献   
5.
In primary visual cortex of hooded rats, pyramidal cells in layer V may be classified as long, medium, or short, on the basis of the layer in which the apical dendrite terminates. The present study determines which of these types of pyramidal cells project to the superior colliculus. Two different strategies were used to label corticotectal cells with horseradish peroxidase (HRP). In the first set of experiments, a large number of corticotectal cells were labeled by retrograde transport following injection of HRP into the superior colliculus. In the second set of experiments, single unit recording was used to identify corticotectal cells physiologically by antidromic activation from the superior colliculus. These cells were then impaled and labeled by intracellular iontophoresis of HRP. The results from both techniques suggest that only long pyramidal cells send an axon to the superior colliculus. These cells are distinguished by an apical dendrite that extends into layer I. We conclude that in hooded rats corticotectal cells in primary visual cortex are the long pyramids in layer V.  相似文献   
6.
In vivo electrochemical methods were employed to study the potassium (K+-evoked release of monoamines from the cerebellum of the chloral hydrate anesthetized rat. K+-evoked releases were elicited using micropipette-Nafion-coated graphite epoxy electrode arrays in the granule/Purkenje cell layer, molecular layer, and white matter. These recorded releases were generally found to be reversible, moderately dose-dependent, and reproducible. However, the temporal dynamics of the releases were different for the cell layer versus molecular layer records. Releases were infrequently observed in cerebellar white matter, an area which is relatively devoid of monoamine containing terminals. The signals recorded from the cell and molecular layers were significantly attenuated by pretreatment with nomifensine, a potent catecholamine reuptake blocker, significantly prolonged the K+-evoked signals observed in both the granule/Purkenje cell and molecular layers. These data, taken together with earlier reports on the electrophysiological responses to activation of cerebellar noradrenergic inputs, support the conjecture that in vivo electrochemical recording methods have the sensitivity and spatial resolution for studies of functional monoamine release from brain regions that have a diffuse or laminated monoamine innervation.  相似文献   
7.
We tested whether hypoglycemia, like hypoxia, would preferentially destroy GABAergic nerve cells in the neocortex. To this end, rat neocortex explants dissected from 6-day-old rat pups and cultured up to a developmental stage approximately comparable to that of the newborn human neocortex, were exposed to hypoglycemia for different periods. Quantitative light microscopic and immunocytochemical evaluation of the cultures demonstrated that hypoglycemia does not preferentially destroy GABAergic but rather non-GABAergic neurons, a finding quite opposite to what was found after hypoxia. Recent biochemical data from other laboratories which seem to support this difference in neuronal vulnerability are discussed. It is concluded that perinatal hypoglycemia may not form such a serious threat with respect to the genesis of epilepsy as does hypoxia.  相似文献   
8.
乌司他丁对大鼠胰性脑病保护作用的实验研究   总被引:12,自引:0,他引:12  
目的 :探讨乌司他丁对大鼠急性出血坏死性胰腺炎时对脑组织损害的保护作用 ,为胰性脑病的治疗提供实验依据。方法 :将 90只SD大鼠随机分为正常对照组 ,急性出血坏死性胰腺炎诱导组和乌司他丁处理组 ,经胰胆管逆行注射 5%牛磺胆酸钠建立大鼠ANP模型 ,12h后处死动物 ,测定血清TNFα水平 ,并检测脑组织含水量、脑微血管内白细胞聚集及附壁现象。结果 :经乌司他丁处理后 ,血清中乌司他丁水平、脑组织含水量、脑组织MDA含量、脑微血管内白细胞聚集及附壁现象显著降低(P <0 .0 1)。结论 :乌司他丁可以减轻急性出血坏死性胰腺炎时脑损害的发生和发展  相似文献   
9.
The immunohistochemical localization of manganese (Mn)-superoxide dismutase (Mn-SOD) was studied in the rat basal forebrain using polyclonal antibodies to Mn-SOD. Neurons of the basal forebrain exhibit a high density of Mn-SOD immunoreactivity. Double immunostaining with a monoclonal antibody to choline acetyltransferase demonstrated that both cholinergic and non-cholinergic neurons in the basal forebrain are intensely immunoreactive for Mn-SOD.  相似文献   
10.
The distribution of elements (e.g. Na, Cl, K) and water in CNS cells is unknown. Therefore, electron probe X-ray microanalysis (EPMA) was used to measure water content and concentrations (mmol/kg dry or wet weight) of Na, Mg, P, S, Cl, K and Ca in morphological compartments of myelinated axons and glial cells from rat optic nerve and cervical spinal cord white matter. Axons in both CNS regions exhibited similar water content ( 90%), and relatively high concentrations (wet and dry weight) of K with low Na and Ca levels. The K content of axons was related to diameter, i.e. small axons in spinal cord and optic nerve had significantly less (25–50%) K than larger diameter axons from the same CNS region. The elemental composition of spinal cord mitochondria was similar to corresponding axoplasm, whereas the water content (75%) of these organelles was substantially lower than that of axoplasm. In glial cell cytoplasm of both CNS areas, P and K (wet and dry weight) were the most abundant elements and water content was approximately 75%. CNS myelin had predominantly high P levels and the lowest water content (33–55%) of any compartment measured. The results of this study demonstrate that each morphological compartment of CNS axons and glia exhibits a characteristic elemental composition and water content which might be related to the structure and function of that neuronal region.  相似文献   
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