地高辛标记的大鼠p75 RNA探针的制备和应用

目的制备用地高辛标记的神经生长因子低亲和力受体(p75)的RNA探针.研究p75在海马组织中的表达.方法设计p75引物,构建p75/pGEM-T重组质粒,分别用ApaⅠ和Sac Ⅰ进行酶切得到线性化DNA片段,以Sp6和T7聚合酶转录合成酶合成地高辛标记的(dig-)正反义RNA探针.运用点膜杂交的方法检验探针的敏感度,运用该探针,通过原位杂交分析p75在海马中的表达.结果构建了p75/pGEM-T质粒,获得高效价的正、反义dig-p75 RNA探针,应用该探针发现p75 mRNA在海马中的表达.结论成功制备了地高辛标记的p75RNA探针,为进一步研究p75在海马中发育和损伤过程中的表达打下基础.     

地高辛标记的小鼠β-1,4-半乳糖基转移酶Ⅰ RNA 探针的制备和应用

为了制备小鼠β-1,4-半乳糖基转移酶I(β-1,4-galactosyltransferase 1,β-1,4-GalT-1)地高辛标记的RNA探针以探讨β-1,4-GalT-I mRNA在坐骨神经组织的表达定位,本研究用提取的小鼠脑总RNA,采用RT-PCR方法,得到β-1,4-GalT-I的DNA片断,将其克隆到pGEM-T载体;采用体外转录的方法合成地高辛标记的正、反义β-1,4-GalT-I RNA探针;运用点杂交的方法分析标记探针的灵敏度;最后应用该探针,通过原位杂交的方法,分析β-1,4-GalT-I mRNA在小鼠坐骨神经的表达.结果:构建了β-1,4-GalT-I/pGEM-T质粒,获得了高效价的地高辛标记的正、反义β-1,4-GalT-I RNA探针,应用该探针发现β-1,4-GalT-J在小鼠坐骨神经髓鞘中有表达.以上结果表明,制备的地高辛标记的正、反义β-1,4-GalT-I RNA原位杂交探针可特异地检测β-1,4-GalT-1 mRNA在组织中的表达.本研究为进一步分析β-1,4-GalT-I在坐骨神经及其它神经组织发育和损伤过程中的表达奠定基础.     

地高辛标记的小鼠β-1,4-半乳糖基转移酶RNA探针的制备和应用

为了制备小鼠 β-1,4-半乳糖基转移酶 ( β-1,4-galactosyltransferase ,β-1,4-Gal T- )地高辛标记的 RNA探针以探讨β-1,4-Gal T- m RNA在坐骨神经组织的表达定位 ,本研究用提取的小鼠脑总 RNA,采用 RT-PCR方法 ,得到β-1,4-Gal T- 的 DNA片断 ,将其克隆到 p GEM-T载体 ;采用体外转录的方法合成地高辛标记的正、反义β-1,4-Gal T- RNA探针 ;运用点杂交的方法分析标记探针的灵敏度 ;最后应用该探针 ,通过原位杂交的方法 ,分析 β-1,4-Gal T- m RNA在小鼠坐骨神经的表达。结果 :构建了β-1,4-Gal T- /p GEM-T质粒 ,获得了高效价的地高辛标记的正、反义β-1,4-Gal T- RNA探针 ,应用该探针发现 β-1,4-Gal T- 在小鼠坐骨神经髓鞘中有表达。以上结果表明 ,制备的地高辛标记的正、反义 β-1,4-Gal T- RNA原位杂交探针可特异地检测β-1,4-Gal T- m RNA在组织中的表达。本研究为进一步分析β-1,4-Gal T- 在坐骨神经及其它神经组织发育和损伤过程中的表达奠定基础。     

地高辛标记的小鼠β—1，4—半乳糖基转移酶IRNA探针的制备和应用

为了制备小鼠β—1，4—半乳糖基转移酶I(β—1，4—galactosyltransferase I，β—1，4—GalT—I)地高辛标记的RNA探针以探讨β—1，4—GalT—I mRNA在坐骨神经组织的表达定位，本研究用提取的小鼠脑总RNA，采用RT—PCR方法，得到β—1，4—GalT—I的DNA片断，将其克隆到pGEM—T载体；采用体外转录的方法合成地高辛标记的正、反义β—1，4—GalT—IRNA探针；运用点杂交的方法分析标记探针的灵敏度；最后应用该探针，通过原位杂交的方法，分析β—1，4—GalT—ImRNA在小鼠坐骨神经的表达。结果：构建了β—1，4—GalT—I／pGEM—T质粒，获得了高效价的地高辛标记的正、反义β—1，4—GalT—IRNA探针，应用该探针发现β—1，4—GalT—I在小鼠坐骨神经髓鞘中有表达。以上结果表明，制备的地高辛标记的正、反义β—1，4—GalT—-RNA原位杂交探针可特异地检测β—1，4—GalT—ImRNA在组织中的表达。本研究为进一步分析β—1，4—GalT—I在坐骨神经及其它神经组织发育和损伤过程中的表达奠定基础。     

正、反义β-1,4半乳糖基转移酶Ⅱ和Ⅴ地高辛标记RNA探针的制备和应用

目的　为了探讨 β1 ,4半乳糖基转移酶 Ⅱ和Ⅴ (β1 ,4 galactosyltransferaseI,β 1 ,4 GalT ⅡandⅤ )表达定位 ,本实验通过分子生物学手段 ,制备正、反义 β 1 ,4 GalT Ⅱ和Ⅴ地高辛标记的RNA原位杂交探针。 方法　设计引物 ,提取小鼠脑总RNA ,通过RT PCR方法 ,得到 β 1 ,4 GalT Ⅱ和Ⅴ基因序列 ,将其克隆到pGEM T载体。根据其多克隆酶切位点和Sp6及T7位置 ,分别酶切后作为转录模板 ,通过Sp6及T7RNA聚合酶 ,得到正、反义 β 1 ,4 GalT Ⅱ和Ⅴ地高辛标记的RNA原位杂交探针。检测标记探针的效价后 ,最后通过原位杂交分析标记探针的特异性和杂交效果。结果　本实验得到了高效价的正、反义 β 1 ,4 GalT Ⅱ和Ⅴ地高辛标记的RNA原位杂交探针 ,并表现出很好的杂交效果。结论　正、反义β 1 ,4 GalT Ⅱ和ⅤRNA原位杂交探针的制备 ,为进一步研究 β 1 ,4 GalT Ⅱ和Ⅴ在组织中的表达 ,尤其在神经组织的定位奠定基础     

大鼠Desert Hedgehog基因的克隆和表达

目的克隆大鼠Desert Hedgehog（DHH）基因,构建其真核表达载体并转染TP67细胞;同时制备DHHcRNA正义及反义探针用于检测其在细胞中的表达。方法提取SD大鼠睾丸总RNA,RT-PCR法扩增DHHcDNA片段,连接于pGEM—TEasy载体,经测序后构建真核表达载体pLXSN／DHH并转染PT67细胞;重组质粒经限制性内切酶NotⅠ和NcoⅠ酶切、回收后,进行转录标记反应,原位杂交检测DHH在嘶7细胞中的表达。结果RT-PCR扩增得到1220bp的片段;成功构建了真核表达载体pLXSN／DHH;制备DHH正义及反义探针浓度分别为150mg／L和80mg／L;DHH在PT67细胞中有表达。结论克隆的DHH基因与大鼠Sertoli细胞的DHH基因相同,成功标记了特异、敏感的DHHcRNA探针,转染的DHH基因能够在PT67细胞中表达。     

人VMAT_2基因RNA探针制备及其在COS-7细胞中的表达

本研究目的在于制备人 型囊泡单胺转运体 (VMAT2 )基因的反义和正义 RNA探针 ,以检测 VMAT2 基因能否在真核细胞表达。从携带 p GEM-Easy-T-VMAT2 克隆载体中通过限制性酶切反应得到 VMAT2 基因 ,与 p BK-RSV载体重组构建真核表达载体 p BK-RSV-VMAT2 ;分别以 T7和 T3聚合酶制备反义和正义探针 ,通过斑点杂交检测探针浓度。转染猴肾成纤维细胞COS-7,原位杂交及免疫荧光细胞化学检测 VMAT2 的表达。结果证明 ,反义和正义探针浓度分别为 80 ng/μl及 12 0 ng/μl;原位杂交及免疫组织化学证实重组的真核表达载体 p BK-RSV-VMAT2 在 COS-7的表达阳性率为 (10 .6± 1.2 ) %。本研究结果表明获得 VMAT2 基因反义链及正义链 RNA探针 ,并检测到 VMAT2 基因在真核细胞中表达     

生后发育过程中睾丸神经生长因子基因的表达

为了通过观察小鼠生后发育过程中睾丸组织神经生长因子 ( NGF)基因表达的变化藉以探讨 NGF在睾丸发育、精子发生过程中的生物学作用 ,本研究采用 RT-PCR方法 ,半定量分析生后 1d、1周、2周、4周及 8周小鼠睾丸组织中 NGF m RNA的表达变化 ;以地高辛标记的βNGF c DNA为探针 ,采用原位杂交法观察 NGF m RNA在幼年及成年小鼠睾丸组织中的分布。 RT-PCR结果显示 ,小鼠生后 1d、1周、2周、4周、8周睾丸组织中均有 NGF m RNA的表达 ,以生后 1周时的表达量为最高。原位杂交结果表明 ,幼年鼠 NGF m RNA杂交信号位于睾丸的间质之中 ,而成年鼠 NGF m RNA杂交信号则主要位于睾丸生精小管管壁和管腔中。结果提示 :NGF m RNA在小鼠出生时即有表达 ,其表达量及在睾丸组织中的分布 ,随小鼠的发育而有变化     

NGF对局灶性脑缺血再灌注大鼠海马CREB表达的上调作用

目的探讨外源性神经生长因子(NGF)对局灶性脑缺血再灌注大鼠海马CREB和磷酸化的CREB(p-CREB)表达的影响。方法用线栓法阻塞大鼠大脑中动脉制作局灶性脑缺血再灌注模型,应用免疫组织化学、W estern B loting和图像分析方法检测大鼠海马CA1区CREB和磷酸化CREB表达。结果假手术组海马CA1区CREB有明显表达,缺血再灌注组CA1区表达较假手术组减少,NGF组CA1区的CREB表达多于缺血再灌注组(P<0.05)。假手术组海马CA1区p-CREB表达很少,缺血再灌注组p-CREB表达多于假手术组,NGF组p-CREB表达多于缺血再灌注组(P<0.05)。结论NGF上调海马CREB和p-CREB的表达,对缺血神经元起保护作用,CREB和p-CREB参与NGF对缺血神经元的保护作用机制。     

小鼠Brd2基因探针的制备及其在荧光原位杂交实验中的应用

目的:为观察溴结构域包含蛋白2(bromodomain containing protein 2,Brd2)基因在小鼠中枢神经系统的表达与分布,本研究制备了两条地高辛标记的Brd2 cRNA探针。方法:提取小鼠脑组织总RNA,设计两对Brd2引物,通过逆转录聚合酶链式反应(RT-PCR)方法,扩增得到两个Brd2的DNA片段,并将它们分别克隆到pCRⅡ-TOPO载体中。利用体外转录方法合成地高辛标记的cRNA探针,最后通过荧光原位杂交实验分析所标记探针的特异性及杂交效果。结果:本实验成功构建了两个Brd2/pCRⅡ-TOPO质粒,获得了特异性的地高辛标记的Brd2cRNA探针,在荧光原位杂交实验中应用两条探针得到了较好的杂交信号。结论:本实验制备的地高辛标记的cRNA探针可特异地检测Brd2 mRNA,为进一步观察Brd2 mRNA在中枢神经系统的分布及功能研究提供了工具。     

Septal cholinergic afferents regulate expression of brain-derived neurotrophic factor andβ-nerve growth factor mRNA in rat hippocampus

Summary In situ hybridization was used to study the expression of members of the nerve growth factor family of trophic factors in rat hippocampus following stimulation of afferent cholinergic and glutamatergic pathways with quisqualate. A transient increase in brain-derived neurotrophic factor (BDNF) and-nerve growth factor (NGF) mRNA expression in the hippocampus was seen 4 h after a quisqualate injection into the medial septal nucleus. Both BDNF and NGF mRNA levels increased more than 4-fold in the granule layer of the dentate gyrus and for BDNF mRNA also in the pyramidal cells of CA1, while the levels of BDNF mRNA in CA3 increased 2-fold. The increase in BDNF and NGF mRNA levels were completely prevented by pretreatment with systemic injections of either scopolamine or diazepam. A quisqualate injection into the entorhinal cortex, containing glutamatergic afferents to the hippocampus, resulted in a 15-, 5- and 17-fold increase in the expression of BDNF mRNA in the ipsilateral granule cells, CA3 and CA1 pyramidal cells, respectively. Similar increases were also seen in the hippocampus contralateral to the injections. In contrast, the level of NGF mRNA did not increase significantly in any of the subfields in the hippocampus. The increase in BDNF mRNA after cortex injections was attenuated by diazepam but not by scopolamine. These findings imply that increased activity in afferent cholinergic and glutamatergic pathways to the hippocampus differentially regulate expression of the NGF family of neurotrophic factors in the hippocampus.     

Early postnatal corticosterone administration regulates neurotrophins and their receptors in septum and hippocampus of the rat

The principal glucocorticoid in rats, corticosterone, interacts with neurons in the limbic system and leads to morphological and behavioral changes. Putative corticosterone-triggered mediators are neurotrophins. In the present study we investigated the effects of early postnatal corticosterone treatment in rats on neurotrophic factors of the nerve growth factor (NGF) family and their receptors. Newborn rats were treated with corticosterone-containing polymers until postnatal day 12. The mRNA and protein levels of the neurotrophins of the NGF family (NGF, BDNF, NT-3 and NT-4/5) and their receptors (trkA, trkB, trkC and p75) were quantified in septum and hippocampus using RT-PCR. In the septal region, we found an unchanged mRNA expression after corticosterone treatment, whereas in the hippocampus there was a general increase in mRNA. Particularly, the gene expression of NGF, NT-3, and the high affinity receptors trkA, trkB and trkC increased significantly. Quantification of the neurotrophin protein levels using an ELISA revealed significant treatment effects for NGF and NT-4/5 in the hippocampus. The present study of corticosterone treatment in young rats demonstrates interactions of steroid hormones with neurotrophic factors and their receptors in the septo-hippocampal system during the first two postnatal weeks.     

降钙素基因相关肽和神经生长因子对局灶性脑缺血再灌注大鼠顶叶、海马FasmRNA表达的影响

目的研究外源性降钙素基因相关肽(CGRP)和神经生长因子(NGF)对局灶性脑缺血再灌注大鼠顶叶、海马FasmRNA表达的影响,探讨降钙素基因相关肽和神经生长因子对缺血再灌注脑神经组织的作用。方法用线栓法制备大鼠大脑中动脉阻塞(MCAO)模型,应用原位杂交和显微图象分析方法检测局灶性脑缺血再灌注大鼠顶叶、海马FasmRNA的表达。结果假手术组大鼠顶叶、海马未见FasmRNA阳性表达细胞;缺血再灌注组(缺血再灌注不同时间段6h,12h,24h,48h,72h)顶叶、海马FasmRNA阳性细胞明显过表达;注射CGRP或NGF后顶叶、海马FasmRNA阳性表达细胞平均光密度值明显低于缺血再灌注组(P<0.01);两者合用组平均光密度值比单独应用低(P<0.05)。结论经颈动脉注入外源性CGRP和NGF下调顶叶和海马缺血神经元FasmRNA的表达,且有协同效应,可能是两者对缺血神经元保护作用的机制之一。     

Immunohistochemical evaluation of the protein expression of nerve growth factor and its TrkA receptor in rat limbic regions following electroshock seizures

Repeated (but not acute) exposure to brief, non-injurious seizures evoked by minimal electroconvulsive shock (ECS) decreases neuronal death in limbic system and increases mRNA levels for nerve growth factor (NGF). Thus, the induction of NGF is a potential mechanism for the neuroprotection evoked by repeated ECS. The neuroprotective action of NGF is mediated by the TrkA receptor. This study determined whether repeated ECS exposure increased TrkA and NGF protein levels. To determine the functional significance of changes in these proteins, we compared the effects of ECS given daily either for 7 days (chronic ECS) or for 1 day (acute ECS). After chronic ECS, upregulation of both NGF and TrkA was found in perirhinal cortex, thalamus, and amygdala. In hippocampus, TrkA was upregulated in CA2, CA3 and CA4. NGF increase in hippocampus was found in CA1 and dentate gyrus. In frontal cortex and substantia innominata, an increase in NGF (but not in TrkA) was found. In most brain regions, TrkA and NGF remained unchanged after acute ECS. Our results demonstrate that repeated exposure to ECS causes an upregulation of TrkA and NGF proteins in several limbic areas in which neuroprotective effects are observed suggesting that NGF contributes to ECS-evoked neuroprotection.     

实验性铅中毒对大鼠海马神经生长因子基因表达的影响

目的观察实验性铅中毒对大鼠海马神经生长因子(NGF)基因表达的影响,探讨铅致学习记忆损害的分子毒理学机制。方法逆转录-多聚酶链反应(RT-PCR)和原位杂交法。结果正常大鼠海马组织可表达NGF mRNA,铅染毒后海马NGF mRNA含量显著下降。海马组织中神经生长因子mRNA表达量与铅染毒时间呈负相关。结论铅可使海马组织神经生长因子基因表达下降。     

Extracellular signal-regulated kinase involved in NGF/VEGF-induced neuroprotective effect

Compelling evidence has shown that extracellular signal-regulated kinase (ERK) is widely expressed in many tissues, including the brain. In the present work, we investigated the temporospatial alterations of ERK1 immunoreactivity in hippocampus and perifocal cortex, and the expression involved in NGF/VEGF-induced neuroprotective effect. We demonstrated that ERK1 expression was first increased in hippocampal CA3/DG 1 h after reperfusion, then it was also increased 6 h after reperfusion in other brain regions, with a peak at day 1-3, and then gradually decreased to basal level at day 14. The expression of caspase-3 was strongly increased 1 h after reperfusion, with peak demonstrated at 3d. NGF/VEGF significantly inhibited the expression of ERK1 and caspase-3. These results suggest that ERK1 signaling pathway may be involved in neuronal cell death and NGF/VEGF-induced neuroprotective effect and there appeared an association between ERK and caspase-3. Inhibition of the ERK signaling pathway might therefore provide an efficient way to prevent neuronal cell death after ischemic cerebral injuries.     

CGRP和NGF对局灶性脑缺血再灌注大鼠海马p53蛋白表达的影响

为了探讨外源性降钙素基因相关肽(CGRP)和神经生长因子(NGF)对局灶性脑缺血再灌注大鼠海马p53蛋白表达的影响,用线栓法制备大鼠大脑中动脉阻塞模型,应用免疫组化和显微图像分析方法检测脑缺血再灌注后大鼠海马CA1区p53蛋白的表达。结果如下:假手术组海马CA1区未见p53阳性细胞,而脑缺血再灌注组阳性细胞明显增多。分别注射CGRP或NGF后海马CA1区p53阳性细胞平均灰度值均明显高于缺血再灌注组(P<0.05),二者联合应用时平均灰度值较单独应用高(P<0.05)。以上结果提示:CGRP和NGF下调缺血神经元p53蛋白的表达,二者合用作用更强,可能对缺血神经元的恢复有促进作用。