三种皮质神经元原代培养方法的改良及对比

目的改良并比较机械分离法、胰蛋白酶消化法和木瓜蛋白酶消化法在大鼠皮质神经元培养中的优缺点,为科技工作者根据各自条件选择合适的培养方法提供理论依据。方法采用胎龄为16~18 d的SD大鼠胚胎,分别用机械分离、胰酶消化以及木瓜蛋白酶消化三种方法对SD胎鼠皮层神经元进行培养,并对不同培养时间的神经元进行形态学观察和免疫荧光显微镜纯度鉴定。结果三种方法均能成功培养出杂质少且纯度高的皮层神经元,其在不同生长阶段具有典型的形态学特征。经NSE免疫荧光染色,神经元纯度分别在96.28%,95.63%及97.34%,三组间无统计学差异(P0.05)。结论三种方法均成功培养出杂质量较少且纯度高的皮层神经元,均可作为神经元体外培养的良好实验模型,且三种培养方法都有其不同的特点。     

SD大鼠骨髓间充质干细胞分离培养及鉴定的实验研究

摘要 目的：探讨应用全骨髓贴壁法体外分离培养SD大鼠骨髓间充质干细胞（BMSCs)的可行性,研究其生物学特性,为骨组织工程提供种子细胞。方法：取SPF级5周龄健康SD大鼠2只,脱颈处死,分离双下肢股骨、胫骨,全骨髓贴壁法分离培养、纯化BMSCs;通过倒置显微镜观察原代、传代细胞生长情况、绘制生长、贴壁率曲线,研究其生物学特性;流式细胞仪检测表面标志物、诱导成成骨等方法进行鉴定。结果：应用全骨髓贴壁法可在体外分离出活性好、纯度高的BMSCs。倒置显微镜下可见原代细胞呈梭形、多角形,传代细胞形态均一呈纤维样;P3代BMSCs经流式细胞鉴定：CD44、CD90高表达,CD31、CD45低表达;定向诱导向成骨细胞分化,可见明显矿化结节。结论：证实应用全骨髓贴壁培养法体外可成功分离BMSCs,所分离培养、纯化的细胞生物学稳定,纯度高、活性好,具有多向分化潜能,能为骨组织工程、骨质疏松症和骨折不愈合疾病的研究提供种子细胞。     

新生SD大鼠皮质神经元的体外培养和鉴定

目的：建立高纯度的新生SD大鼠皮质神经元原代培养方法。方法：取24h内的新生SD大鼠皮质,用木瓜酶和DNaseⅠ共同消化,5％胎牛血清终止消化,吹打分离组织获得单细胞悬液,进行细胞计数,用无血清DMEM／F12种植培养,4h后换成用无血清Neurobasal配制的维持培养液继续培养,尼氏小体染色和免疫荧光法鉴定神经元的纯度。结果：培养第10d,神经元胞体饱满,结构清晰完整,光晕明显,折光性强,可见粗长的树突和轴突,相邻细胞形成紧密网状联系,神经元纯度达到96％以上。结论：经改良和优化,无须添加阿糖胞苷抑制胶质细胞的生长即能够获得生长状态良好、高纯度的神经元。     

小鼠小脑颗粒神经元的原代培养与鉴定

本研究通过体外分离培养及鉴定原代小鼠小脑颗粒神经元(cerebellar granule neurons,CGNs),为神经科学研究提供原代神经元细胞模型。取生后第7天的ICR乳鼠小脑,在解剖体视镜下剥离脑膜及血管,经刀片切碎、0.25%胰酶消化、移液器吹打、70μm尼龙滤网制备单细胞悬液,差速贴壁后接种于新鲜配置的培养基。倒置相差显微镜观察不同时间CGNs的形态变化。采用神经元的标记蛋白微管相关蛋白-2(microtubule associated protein 2,MAP2),星形胶质细胞的标记蛋白胶质纤维酸性蛋白(glial fibrillary acidic protein,GFAP),小胶质细胞的标记蛋白(type 3 complement receptor,CR3/CD11b)进行免疫荧光检测培养的原代CGNs纯度。原代培养CGNs接种20 min后即贴壁良好,培养24 h后细胞伸出突起,培养第7天神经元成熟,形成丰富的轴突,树突和胞间突触连接。经免疫荧光鉴定,CGNs纯度可达95%以上。成功体外分离培养出高纯度的原代CGNs,可应用于CGNs的体外研究。     

高效的多巴胺能神经元原代培养方法及其影响因素的研究

目的：建立一种简单高效的中脑多巴胺神经元细胞原代培养方法,并观察胰酶消化对中脑多巴胺能神经元突起生长的损伤作用。方法：以Nakai等经典神经元细胞原代培养方法为基础,通过使用低日龄胎鼠,初次培养液加入胎牛血清等步骤,促进中脑多巴胺能神经元细胞贴壁和生长;在无胰酶消化组直接使用内口外翻的小口径硅化吸管轻柔吹打离散细胞,比较两种方法间神经元细胞突起形成的差异。结果：接吹打组其多巴胺能神经元细胞突起的生长程度（2124-10um）明显高于胰酶消化组（113＋9μm）（P〈0．01）,而两组间多巴胺阳性细胞比例未见显著差异（P〉0．05）。结论：在中脑多巴胺能神经元细胞原代培养中,低日龄胎鼠及免胰酶消化离散细胞可减少神经元细胞损伤,有利于细胞突起的生长。     

成年SD大鼠心肌原代成纤维细胞分离及培养的优化方案

目的:摸索及优选成年SD大鼠心肌原代成纤维细胞的体外分离、培养及鉴定的实验方法。方法:将成年SD大鼠心脏剪成小组织块,采用以下四种方案(A:0.08%胰酶+0.1%胶原酶II消化15 min,B:0.2%胶原酶II消化15 min,C:0.2%胶原酶II消化60min,D:0.2%胶原酶II消化90 min)提取成年大鼠心脏原代成纤维细胞,再通过差速贴壁分离方法培养原代成纤维细胞。采用倒置显微镜观察成纤维细胞的基本形态特征,并进行Vimentiin免疫荧光染色对培养的原代细胞进行荧光鉴定;采用台盼兰染色对培养的原代成纤维细胞存活率进行鉴定;采用细胞计数对培养的成纤维细胞生长趋势进行鉴定。结果:四种方法均能培养成纤维细胞,但单酶消化60 min可一次性提取较多细胞,并且细胞状态佳,3 d即可传代。72 h成纤维细胞Vimentin免疫荧光染色阳性率高达97%。台盼兰染色可见其细胞死亡率明显降低,并且细胞计数可见细胞生长状态极佳。结论:单酶消化60 min是提取成年SD大鼠心肌原代成纤维细胞的高效、快速、稳定的实验方法,为心脏疾病的基础及临床研究提供了较为理想的细胞学实验模型。     

密度梯度离心法同时分离新生大鼠原代心肌细胞与成纤维细胞

本文旨在探讨一种改良的同时分离新生大鼠原代心肌细胞和成纤维细胞的方法,以建立良好的原代心肌细胞及成纤维细胞研究模型。无菌状态下取Wistar乳鼠(出生不超过2天)心室,用II型胶原酶消化,控制消化时间及次数、搅拌速度、离心次数和速度等,结合Percoll密度梯度离心法分离心肌细胞及成纤维细胞,进行体外培养,观察细胞形态,继而用0.2%台盼蓝染色检测细胞存活率,免疫荧光染色法检测心肌肌钙蛋白I(cardiac troponin I,c Tn I)、波形蛋白(Vimentin)及α平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)的表达,分别用于鉴定心肌细胞和成纤维细胞纯度。结果显示,本方法5次分离的心肌细胞平均存活率达92%,纯度达95%以上,细胞生长状态良好,可见贴壁自发搏动;成纤维细胞平均存活率达96%,纯度达94%。本方法能同时获得新生大鼠原代心肌细胞和成纤维细胞,具有很高的产量、存活率及纯度,且操作简便,耗时短,重复性好,是一种较为理想的原代细胞分离、培养方法,可满足各种后续实验要求。     

顺铂耳毒性大鼠耳聋模型的研究

摘要 目的：探讨顺铂对大鼠造成的听力损伤及耳蜗细胞形态学变化。方法：体内实验,运用顺铂腹腔注射的方法,连续七天注射,通过听性脑干反应检测,观察顺铂对不同日龄的大鼠听力损伤情况;测听后取耳蜗,通过基底膜铺片和冰冻切片的免疫荧光染色,观察听力损伤后对耳蜗毛细胞和螺旋神经元的影响。体外实验,耳蜗器官培养免疫荧光染色,观察顺铂对耳蜗毛细胞和螺旋神经元的影响。结果：顺铂具有耳毒性,会对大鼠听力造成损伤,高频听力损伤更加严重,而且对不同日龄的大鼠造成的听力损失不同,小日龄的大鼠对顺铂耳毒性更加敏感。体内实验,顺铂耳毒性造成听力损失,会引起大鼠耳蜗毛细胞的缺失,但未观察到明显的螺旋神经元缺失,也没有观察到明显的Cleaved caspase-3阳性螺旋神经元细胞。体外实验,可以观察到顺铂同时引起毛细胞和螺旋神经元产生明显的损伤。结论：体、内外实验,都可以建立稳定的顺铂耳毒性大鼠耳聋模型,对研究顺铂损伤耳蜗毛细胞的发生机制和保护奠定了实验基础。     

大鼠骨髓间充质干细胞的原代培养及鉴定

摘要 目的：研究大鼠BMSCs（骨髓间充质干细胞）原代培养与纯度鉴定的方法。方法：无菌环境中,从SD大鼠股骨与胫骨端采集骨髓,先行酶消化,利用全骨髓细胞悬液贴壁法对提取BMSCs实施传代培养,选取生长良好的第3代细胞进行鉴定;对BMSCs实施成脂与成骨诱导分化,同时经由油红O（ORO）与茜素红（ARS）染色法对诱导分化效果加以鉴定;借助流式细胞术（FCM）对CD34、CD44与CD90这3类BMSCs表面标志物的表达展开分析。结果：BMSCs是长梭状贴壁细胞,生长状态为纤维细胞样漩涡状;在第3代BMSCs传代期间,其第1-3 d发展至生长潜伏期,呈较慢速的生长;第3-5 d发展至对数生长期,呈高速生长;待至第7 d长速增殖最大,速度停止上升进入平缓期;BMSCs成骨、成脂诱导结束后,对其诱导分化鉴定发现：细胞出现明显形态学变化,通过ORO对脂肪染色,细胞显示橘红色;待成骨诱导培养结束,通过ARS对钙盐染色,显示红色,且出现矿化结节沉积,说明BMSCs具有良好的成骨、成脂分化能力;FCM测定发现：CD34表达呈阴性（1.09 %）,CD90（96.8 %）与CD44（92.4 %）皆呈阳性,与BMSCs表型相符。结论：经由全骨髓黏附培养技术有效分离BMSCs,且完成培养。     

慢病毒介导的GFP转染对大鼠骨髓间充质干细胞增殖、细胞表型及脑脊液诱导后分化能力的影响

摘要 目的：研究慢病毒（Lentivirus）介导的绿色荧光蛋白（Lentivirus-GFP）转染大鼠骨髓间充质干细胞（BMSCs）的可行性及稳定性,以及对人脑脊液诱导转染后BMSCs（BMSCs-GFP）成神经分化能力的影响。方法：全骨髓贴壁法培养BMSCs,Lentivirus-GFP以5、10、30、50的感染复数（MOI）转染BMSCs,96h后倒置显微镜下观察GFP转染效率和表达情况,筛选最适MOI;流式细胞术检测细胞表型;CCK8法检测细胞活力。人脑脊液诱导BMSCs-GFP向神经细胞分化,蛋白印迹法检测神经细胞表面标记物MAP-2和Nestin表达。结果：全骨髓贴壁法分离培养的BMSCs生长旺盛。MOI值为5、10、30、50的转染效率分别为56.2%、87.3%、94.7%和95.1%,当MOI为30时,Lentivirus-GFP转染BMSCs效率较高,且对BMSCs生长状态无显著性影响。BMSCs-GFP表达CD29、CD90,较少表达CD45、CD54,符合干细胞特性。BMSCs-GFP增殖活性与未转染GFP基因的BMSCs相比,差异无统计学意义（P>0.05）。人脑脊液诱导BMSCs-GFP成神经细胞分化后表达神经元标记物MAP-2和Nestin。结论：Lentivirus-GFP能高效稳定转染大鼠BMSCs（最适MOI值为30）,同时不影响其生物学特性,人脑脊液能诱导BMSCs-GFP成神经细胞分化。     

Epileptiform postsynaptic currents in primary culture of rat cortical neurons: Calcium mechanisms

In this study we demonstrate that the primary culture of rat cortical neurons is a convenient model for investigations of epileptogenesis mechanisms and specifically, of the postsynaptic epileptiform currents (EC) reflecting periodical asynchronous glutamate release. In particular, we have revealed that in primary culture of cortical neurons EC can appear spontaneously or can be triggered by the withdrawal of magnesium block of NMDA receptor channels or by shutting down GABAergic inhibition. EC were found to depend on intracellular calcium oscillations. The secondary calcium release from intracellular stores was needed for EC synchronization. EC were suppressed by the influences causing either neuronal calcium overload or decrease of intracellular calcium concentration. Calcium entry into neurons in the case of NMDA receptor hyperactivation or in the case of calcium ionophore ionomycin treatment eliminated EC. The suppression of EC also occurred after a decrease of intracellular calcium concentration induced by BAPTA loaded into the neurons or by stimulation of calcium removal from cells via Na⁺/Ca²⁺ exchanger by 1 nM ouabain. Partial dependence of EC on action potential generation was found. Thus, EC in neurons are activated by intracellular periodic calcium waves within a limited concentration window.     

树鼩脑星形胶质细胞的体外培养及纯化

本文旨在建立低等灵长类动物树鼩(Tupaia belangeri)脑星形胶质细胞(astrocyte,AS)原代培养及纯化的技术,为利用新型实验动物树鼩进行研究工作而建立体外模型。将新生树鼩大脑皮质机械分离,置于4°C冰箱20min以损伤神经元,皮质组织块用胰蛋白酶消化后制成细胞悬液,分次贴壁去除成纤维细胞,培养的混合细胞在每次换液时用0.005%胰蛋白酶轻柔漂洗去除神经元。细胞长满培养瓶底面积约70%时,用0.025%胰酶溶液静置消化,至肉眼可见一层白色薄膜从瓶底脱落时终止消化,此白色薄膜即为AS层。AS传至第三代时,用抗胶质纤维酸性蛋白(glial fibrillary acidic protein,GFAP)抗体进行免疫组织化学染色和免疫荧光染色鉴定。结果显示,本方法所得的树鼩脑AS的纯度可达98%以上。该结果提示,这种通过分次贴壁法结合差异消化的培养及纯化技术可获得高纯度的树鼩脑AS,为建立神经系统疾病新的体外细胞培养模型打下了基础。     

Resveratrol promotes cellular glucose utilization in primary cultured cortical neurons via calcium-dependent signaling pathway

Background and PurposeImpairment of glucose utilization contributes to neuronal degeneration of Alzheimer's disease patients. Cellular glucose utilization can be regulated by calcium-dependent signaling pathways. Resveratrol (RSV) is a plant-derived polyphenol with multiple beneficial effects, including neuroprotection and metabolic improvement. Here, we investigated the effect of RSV on neuronal calcium signal and glucose utilization.Experimental MethodsPrimary culture of cortical neurons, calcium imaging, 2-NBDG assay and western blotting were employed to investigate RSV-mediated effects on neuronal calcium signal and glucose utilization.ResultsRSV elevated intracellular calcium in cortical neurons via modulation of secondary messenger system including nitrous oxide, cGMP and cAMP. Secondarily, a calcium-dependent enhancement of neuronal glucose utilization after RSV treatment was observed. The effects on neuronal glucose utilization are largely dependent on RSV-induced calcium-dependent AMP-activated protein kinase activation.ConclusionOur findings show that activation of calcium-dependent signaling pathways by RSV may convey improvements of neuronal glucose utilization.     

豚鼠肾小管上皮原代细胞的培养

目的建立一种简便易行的豚鼠原代肾小管上皮细胞培养方法。方法运用筛网分离法和多种酶消化法获取高纯度的肾小管上皮细胞。利用免疫组化法和形态学观察法鉴定培养的肾小管上皮细胞性质及纯度。结果通过肾小管节段贴壁,胶原酶消化组织节段和细胞等方法,有效地促进肾小管原代细胞增殖;胰酶节段消化法的细胞贴壁效果稍差,细胞传代状态不理想;胰酶消化法则细胞贴壁较少,细胞生长状态较差。结论培养豚鼠原代。肾小管上皮细胞是可行的。     

Intermittent Hypothermia Is Neuroprotective in an in vitro Model of Ischemic Stroke

Objective: To investigate whether the intermittent hypothermia (IH) protects neurons against ischemic insult and the potential molecular targets using an in vitro ischemic model of oxygen glucose deprivation (OGD).Methods: Fetal rat cortical neurons isolated from Day E18 rat embryos were subjected to 90-min OGD and hypothermia treatments during reoxygenation before examining the changes in microscopic morphology, cell viability, microtubule- associated protein 2 (MAP-2) release, intracellular pH value and calcium, reactive oxygen species (ROS) generation, mitochondrial membrane potential (△Ψm) and neuronal death using cell counting kit (CCK-8), enzyme-linked immunosorbent assay (ELISA), BCECF AM, Fluo-3 AM, DCFH-DA and dihydroethidium (DHE), JC-1 staining and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL), respectively.Results: 90-min OGD induced morphologic abnormalities, cell viability decline, MAP-2 release, intracellular acidosis, calcium overload, increased ROS generation, △Ψm decrease and cell death in primary neurons, which was partially inhibited by continuous hypothermia (CH) and intermittent hypothermia (IH). Interestingly, 6-h CH was insufficient to reduce intracellular calcium overload and stabilize mitochondrial membrane potential (△Ψm), while 12-h CH was effective in reversing the above changes. All IH treatments (6×1 h, 4×1.5 h or 3×2 h) effectively attenuated intracellular free calcium overload, inhibited ROS production, stabilized mitochondrial membrane potential (△Ψm) and reduced delayed cell death in OGD-treated cells. However, only IH intervals longer than 1.5 h appeared to be effective in preventing cell viability loss and intracellular pH decline.Conclusion: Both CH and IH were neuroprotective in an in vitro model of ischemic stroke, and in spite of shorter hypothermia duration, IH could provide a comparable neuroprotection to CH.     

东方田鼠皮肤成纤维细胞的分离培养及生物学特性

目的探索和建立东方田鼠皮肤成纤维细胞体外分离、培养的技术方法并观察其生物学特性。方法采用含10%小牛血清的Dulbecco改良Eagle培养液(DMEM)和1640两种培养体系,运用组织块贴壁法和胰酶消化法,分别对出生后1、3 d和5 d的东方田鼠乳鼠皮肤成纤维细胞进行原代分离、培养。苏木素-伊红染色及倒置相差显微镜下观察成纤维细胞形态和生长特性。结果 0.25%胰酶消化分离出生后1 d和3 d东方田鼠乳鼠皮肤较出生后5 d组织可获得较多数量细胞,成纤维细胞在体外快速贴壁生长,一般6～7 d长满培养瓶,细胞纯度高,HE染色细胞呈长梭形,胞核明显;DMEM和1640两种培养液均可用于东方田鼠皮肤成纤维细胞的培养,但细胞传代后生长趋缓,只可传代2～3次。本实验运用组织块贴壁法未能培养出皮肤成纤维细胞。结论确定了有效分离东方田鼠皮肤成纤维细胞的日龄和方法,为进一步深入研究提供了技术方法和操作依据。     

A possible pivotal role of mitochondrial free calcium in neurotoxicity mediated by N-methyl-d-aspartate receptors in cultured rat hippocampal neurons

We have previously shown that mitochondrial membrane potential disruption is involved in mechanisms underlying differential vulnerabilities to the excitotoxicity mediated by N-methyl-d-aspartate (NMDA) receptors between primary cultured neurons prepared from rat cortex and hippocampus. To further elucidate the role of mitochondria in the excitotoxicity after activation of NMDA receptors, neurons were loaded with the fluorescent dye calcein diffusible in the cytoplasm and organelles for determination of the activity of mitochondrial permeability transition pore (mPTP) responsible for the leakage of different mitochondrial molecules. The addition of CoCl₂ similarly quenched the intracellular fluorescence except mitochondria in both cultured neurons, while further addition of NMDA led to a leakage of the dye into the cytoplasm in hippocampal neurons only. An mPTP inhibitor prevented the NMDA-induced loss of viability in hippocampal neurons, while an activator of mPTP induced a similarly potent loss of viability in cortical and hippocampal neurons. Although NMDA was more effective in increasing rhodamine-2 fluorescence as a mitochondrial calcium indicator in hippocampal than cortical neurons, a mitochondrial calcium uniporter inhibitor significantly prevented the NMDA-induced loss of viability in hippocampal neurons. Expression of mRNA was significantly higher for the putative uniporter uncoupling protein-2 in hippocampal than cortical neurons. These results suggest that mitochondrial calcium uniporter would be at least in part responsible for the NMDA neurotoxicity through a mechanism relevant to promotion of mPTP orchestration in hippocampal neurons.