大鼠视交叉上核至视上核的纤维联系—免疫组化双重标记法研究

为了观察视交叉上核（SCN）的传出纤维，本实验采用兔抗VIP及AVP血清作为一抗对大鼠下丘脑SCN与视上核（SON）进行免疫组化双重染色研究，结果观察到在SCN尾段，位于腹侧份的VIP样神经纤维走向SON，而在SON的腹侧份的VIP样神经纤维走向SON，而在SON的腹侧份及背侧份可见VIP样纤维分布，并明显可见该纤维包绕AVP样神经元周围,由此本推测在SCN至SON之间可能存在直接的纤维联系，它可能是体内血浆和神经垂体的加压素（VP），催化素（OT）水平呈现24小时节律的又一原因。     

加压素在自发性高血压大鼠与正常大鼠下丘脑视上核、室旁核神经元内表达

目的观察加压素(AVP)在自发性高血压大鼠(SHR)与正常大鼠下丘脑视上核(SON)、室旁核(PVN)内的分布。方法应用光镜和免疫细胞化学技术。结果SHR的AVP阳性细胞内分泌颗粒密集呈棕黄色,正常大鼠组则染色较浅。SHR大鼠SON内AVP阳性神经元百分数(69.30±18.10%)明显多于正常大鼠(59.53±16.97%,P<0.05),而两组大鼠PVN内AVP的表达无明显差异。结论AVP在下丘脑的血压调节活动中起着重要的介导作用,中枢AVP含量的异常增加可能与高血压的发病有关。     

IFN-γ对流产大鼠视上核、弓状核、室旁核TNF-α表达的影响

为了探讨γ-干扰素(IFN-γ)对流产大鼠视上核(SON)、弓状核(AN)、室旁核(PVN)内肿瘤坏死因子α(TNF-α)表达的影响,将20只孕SD大鼠随机分为A、B、C、D组。A组为对照组;B组为流产模型组;C、D组分别为流产模型+1IU/gIFN-γ组和流产模型+10IU/gIFN-γ组。妊娠13d灌注取材,并观察妊娠结局;采用免疫组化SP法对每组SON、AN、PVN中TNF-α的表达进行检测。结果显示:B、C、D组三个核团内TNF-α免疫阳性产物的灰度值均较A组降低,而阳性细胞数均较A组增高;C组SON、AN内TNF-α的阳性灰度值均高于B组,而SON、AN、PVN阳性细胞数均低于B组;D组TNF-α免疫阳性产物的灰度值均较B、C组低,阳性细胞数均较B、C组高;C组平均胚胎数较B、D组显著增高。以上结果表明IU/gIFN-γ对妊娠有利,这种作用可能与其参与SON、AN和PVN中TNF-α表达的调节有关。     

外源性雌激素对去势后大鼠下丘脑视上核一氧化氮合酶阳性神经元分布的影响

目的观察外源性雌激素对去势后雌性大鼠下丘脑视上核(SON)一氧化氮合酶(NOS)阳性神经元分布的影响。方法选用2～3月龄、健康未交配的雌性大鼠40只;动物分组如下:对照组大鼠20只,分为正常对照组(n=10)和实验对照组(卵巢切除术后,n=10)。实验组(即卵巢切除术后肌肉注射雌激素组)20只,造模成功后,分别于术后40d(即给药一个月)和术后70d(即给药两个月)陆续灌注取材。采用SABC法在光学显微镜下对下丘脑视上核内NOS阳性神经元进行形态学观察和细胞计数,采用图像分析系统测定NOS阳性神经元内免疫反应产物的平均灰度值。结果卵巢切除术后对照组大鼠下丘脑视上核NOS阳性神经元的密度明显增高,细胞比正常对照组有所增大(P0.05)。去势后补充雌激素1个月组的大鼠与正常对照组和卵巢切除组相比较,视上核内NOS阳性神经元的密度及形态均无明显改变(P0.05)。去势后补充雌激素两个月组与实验对照组相比较,无论NOS阳性神经元的密度还是阳性神经元胞体的大小均显著下降(P0.05),细胞着色变浅。结论外源性雌激素可能影响去势雌性大鼠下丘脑视上核NOS阳性神经元的分布和表达。     

大鼠侧脑室注射甘珀酸后下丘脑视上核星形细胞和神经元对高渗刺激反应的影响

目的 观察大鼠侧脑室注射甘珀酸后下丘脑视上核星形细胞和神经元对高渗刺激反应的影响。方法 经侧脑室注射缝隙连接阻断剂甘珀酸(carbenoxolone,CBX)及尾静脉注射9％NaCl溶液后，用放射性免疫分析法测定大鼠血浆中加压素(VP)含量，免疫组织化学方法观察下丘脑视上核(SON)神经元的：Fos和星形细胞的Fos以及胶质原纤维酸性蛋白(GFAP)表达的变化。结果 1．未注射CBX组大鼠在高渗刺激后45min，血浆中VP的含量明显升高；SON中观察到GFAP／Fos阳性的星形细胞和Fos阳性神经元；2．GFAP／Fos阳性星形细胞高峰的出现早于Fos阳性神经元；3．向侧脑室注射CBX2h后，经尾静脉注射9％NaCl溶液，45Bin后血浆中的VP含量未升高，SON中GFAP／Fos阳性星形细胞的表达与未注射CBX组相同，Fos阳性神经元则显著减少。结论 SON的星形细胞对高渗刺激发生反应早于神经元，并可能通过缝隙连接影响神经元对渗透压的调节功能。     

心理应激对大鼠胃窦生长抑素mRNA细胞的影响

<正> 为探讨心理因素对胃窦粘膜生长抑素mRMA细胞的影响,本文采用Yanjin等创建的方法,以雄性SD大鼠15只,随机等分成 A、B、C三组,建立心理应激动物模型.以原位杂交组织化学技术和微机图像分析技术(Tiger图像分析软件),检测大鼠心理应激后胃窦粘膜生长抑素mRNA阳性细胞的表达强度和细胞体积密度(Vv)、单位体积数密度(Nv)的变化.结果表明:A、B两且大鼠胃窦粘膜生长抑素mRNA细胞的阳性表达信号明显强于只给无规律闪兴刺激的C组;阳性细胞的Vv和Nv方面,三组相比,为闪光间期长短不均加电刺激组(A组)>闪光间期衡定加电刺激组(B组)>单纯闪光间期长短不均组(C组).此结果揭示了心理应激后胃窦粘膜D细胞合成、分泌生长抑素是增加的.本实验从基因的量变角度揭示了心理应激后胃窦粘     

腹腔注射2-脱氧-D-葡萄糖可诱发大鼠视上核和室旁核神经元表达Fos

目的 探讨腹腔注射2-脱氧-D-葡萄糖（2-DG）能否激活大鼠下丘脑视上核（SON）和室旁核（PVN）神经元而表达Fos。方法 健康雄性SD大鼠12只,随机分为腹腔注射2-DG组（6只）、生理盐水对照组（3只）及正常对照组（3只）。各自处理后,应用免疫组织化学方法,观察各组下丘脑SON和PVN内Fos表达及其与催产素（OT）和加压素（VP）的双标情况,同时采用ELISA方法对血清中OT和VP的含量进行检测。 结果与生理盐水对照组和正常对照组相比,2-DG引发的特异性Fos免疫阳性产物主要集中分布于下丘脑外侧区和穹隆周区,在SON、PVN也有密集表达。SON和PVN内的Fos表达与该区的特异性神经活性物质OT和VP有共存。OT/Fos双标细胞率（双标细胞占OT阳性细胞的百分率）在SON和PVN分别为87.10%、90.57%,明显高于VP/Fos在这两个核团的双标率（双标细胞占VP阳性细胞的百分率,68.42%、76.92%）,两者比较差异有统计学意义（P<0.05）。ELISA检测结果显示,2-DG组动物血清中OT和VP水平与对照组相比无明显变化。 结论 腹腔注射2-DG可激活大鼠下丘脑SON和PVN内OT和VP神经元表达Fos,SON和PVN可能参与2-DG诱导的急性应激反应。     

精氨酸加压素阳性神经元在大鼠下丘脑的定位

目的:观察大鼠精氨酸加压素(AVP)及其mRNA阳性神经元在下丘脑的分布和形态特征。方法:以尼氏染色作参照,运用免疫组化和原位杂交观察AVP及其mRNA在下丘脑的表达。结果:下丘脑AVP及其mRNA阳性的神经元由吻侧到尾侧依次出现于视上核,视上核和视交叉上核,视上核、视交叉上核和室旁核,视上核和室旁核及视上核、下丘脑前核和室旁核。AVP及其mRNA阳性神经元仅占据视上核背内侧;在第三脑室室管膜膜内或膜下可见AVP阳性神经元的胞体或突起;在不同核团内AVP阳性神经元的形态存在差异。结论:AVP及其mRNA阳性神经元在下丘脑不同核团内具有特异性分布;AVP阳性触液神经元可能是调节脑脊液和脑组织之间AVP含量的桥梁。     

低渗刺激下大鼠视上核星形胶质细胞对神经元反应的调控机制

目的观察低渗刺激后大鼠视上核(SON)星形胶质细胞对神经元反应的调节机制,以及牛磺酸拮抗剂(TAG)和缝隙连接阻断剂-甘珀酸(CBX)对反应的影响。方法成年SD大鼠20只,对照组经尾静脉注射0.9%盐水;低渗组经尾静脉注射低渗盐水(0.83%葡萄糖 0.3%NaCl);TAG 低渗组和CBX 低渗组分别经侧脑室注射TAG或CBX,2h后经尾静脉注射低渗盐水。常规固定取材制片。切片进行抗Fos、抗加压素(VP)、抗甘氨酸受体(GlyR)、抗胶质原纤维酸性蛋白(GFAP)、抗缝隙连接蛋白43(Cx43)免疫荧光染色,镜下观察在视上核神经元和星形胶质细胞的表达。结果低渗组视上核星形胶质细胞的GFAP和Cx43表达高于对照组,GlyR阳性神经元较对照组多,Fos和VP阳性神经元较对照组少;TAG 低渗组和CBX 低渗组,星形胶质细胞的反应同低渗组,而GlyR阳性神经元较低渗组少,VP-、Fos-阳性神经元较低渗组均有所增加。结论低渗刺激激活视上核星形胶质细胞,被激活的星形胶质细胞可能经缝隙连接释放牛磺酸而抑制神经元,减少VP的释放,此过程可被TAG和CBX所阻断。     

LPS对大鼠下丘脑视上核nNOS和c-fos表达的影响

为探讨下丘脑视上核(SON)在神经免疫调节中的作用,本实验应用免疫组化技术观察了腹腔注射脂多糖(LPS)后大鼠下丘脑视上核nNOS和c-fos表达的变化。结果表明:LPS可使大鼠视上核内nNOS和c-fos阳性细胞的OD值显著增高,且视上核内部分神经元可同时表达nNOS和c-fos。结果提示,视上核可能为免疫调节的高级整合中枢之一,可能通过NO和／或c-fos途径调节免疫功能。     

心理应激对大鼠下丘脑室周核生长抑素mRNA神经元的影响

目的：探讨心理应激因素对下丘脑室周核生长抑素ｍＲＮＡ阳性神经元的影响。材料和方法：采用心理应激大鼠模型，以原位杂交组织化学及图像分析技术，检测下丘脑室周核生长抑素ｍＲＮＡ阳性神经元的表达程度和神经元体积密度及单位体积细胞数密度的变化。     

In situ hybridization analysis of vasopressin mRNA expression in the mouse hypothalamus: Diurnal variation in the suprachiasmatic nucleus

The distribution, and diurnal variation of AVP mRNA-expressing neurons in the hypothalamus of the mouse has been investigated using in situ hybridization histochemistry. In general, cells hybridizing with an AVP mRNA-specific oligonucleotide probe in the mouse hypothalamus exhibit a similar distribution to the well-characterized distribution of AVP nuclei in the rat, but species-specific patterns of expression have been observed, a finding that confirms the results of earlier immunocytochemical studies. For example, prominent groups of AVP mRNA expressing cells are found in the region between the paraventricular (PVN) and suprachiasmatic (SCN) nuclei, forming the distinct mouse accessory nucleus, and a periventricular group that merges with the PVN neurons. Sampling of brains during both phases of the daily cycle (either 10.00 h (light) or 22.00 h (dark)) revealed a marked and significant variation in AVP mRNA abundance in the SCN whereas a similar variation was not consistently observed in the magnocellular neurons of the supraoptic nucleus (SON). This study has confirmed the distribution of AVP-synthesizing neurons in the mouse hypothalamus, and provided an anatomical substrate for molecular genetic studies in this species that are designed to investigate the basis of neuronal rhythmicity.     

视上核内电针和注射谷氨酸对脑部核团加压素含量的RIA

本工作应用ＲＩＡ观察了在视上核为注射１０μｇＬ－谷氨酸和电针对脑部核团精氨酸加压素含量的变化。     

Neurohypophyseal peptides in aging and Alzheimer's disease

The neurohypophyseal hormones arginine-vasopressin (AVP) and oxytocin (OT) are produced in the neurons of the hypothalamic supraoptic (SON) and paraventricular (PVN) nucleus and in the much smaller cells of the suprachiasmatic (SCN) nucleus. The SON is the main source of plasma AVP. Part of the AVP and OT neurons of the PVN join the hypothalamo-neurohypophyseal tract, whereas others send projections to the median eminence or various brain areas, where AVP and OT are involved in a number of central functions as neurotransmitters/neuromodulators. AVP and OT from the PVN can also regulate via the autonomous innervation endocrine glands and fat tissue. OT is produced for a major part in the PVN but some OT neurons are present in the SON. Moreover, both AVP and OT containing neurons are observed in the "accessory nuclei", i.e. islands situated between the SON and PVN. The SCN is the biological clock, and the number of AVP expressing neurons in the SCN shows both diurnal and seasonal rhythms. In addition to these hypothalamic areas, AVP and OT may be found to a lesser extent in some other brain areas, such as the bed nucleus of the stria terminalis, diagonal band of Broca, nucleus basalis of Meynert, lateral septal nucleus, globus pallidus and the anterior amygdaloid nucleus, as well as in the peripheral tissues. The AVP and OT containing neurons should not be considered as one system. Prominent functional differences exist between the different nuclei. The heterogeneity also becomes clear from the marked differences in the neurohypophyseal peptides containing neurons of the SON, PVN and SCN during aging, and in the most prevalent age-related neurodegenerative diseases, i.e. Alzheimer's disease (AD). For those reasons, we will discuss the SON, PVN and SCN separately.     

不同月龄大鼠视上核血管加压素分泌的比较研究

我们应用光电镜技术、免疫细胞化学技术和图象分析技术对不同月龄大鼠视上核神经元ＡＶＰ的分泌进行了比较研究。结果：电镜下老龄组神经元胞质内脂褐素较多;ＰＡＰ法显示成龄组ＡＶＰ阳性细胞染色呈深棕色;数据经统计学处理有显著性差异,提示成龄组分泌功能较强而老龄组分泌功能减弱。     

The single-prolonged stress paradigm alters both the morphology and stress response of magnocellular vasopressin neurons

Vasopressin (AVP) plays an important role in anxiety-related and social behaviors. Single-prolonged stress (SPS) has been established as an animal acute severe stress model and has been shown to induce a lower adrenocorticotropic hormone (ACTH) response upon cortisol challenge. Here, we show results from immunoassays for AVP, ACTH, and corticosterone (CORT), and in situ hybridizations for AVP mRNA performed 7 days after SPS exposure. Immunofluorescence for AVP was also performed during the 7-day period following SPS exposure and after an additional forced swimming stress paradigm. We observed that the plasma concentrations of AVP, ACTH, and CORT were not altered by SPS; ACTH content in the pituitary and AVP mRNA expression in the supraoptic nucleus (SON) were significantly reduced by SPS. During the 7-day period following SPS, the intensity of immunoreactivity, the size of the soma, and the immunoreactive optical density of the dendrites of AVP neurons in the SON all increased. An apparent reduction in the intensity of AVP immunoreactivity was observed in the SON at 4 h after additional stress. Additional forced swimming led to a rapid increase in the dendritic AVP content only in the controls and not in the SPS-treated rats. These findings suggest that AVP is a potential biomarker for past exposure to severe stress and that alterations in AVP may affect the development of pathogenesis in stress-related disorders.     

视网膜节细胞投射到视交叉上核AVP神经元的研究——假狂犬病毒跨神经元追踪结合胶体金免疫电镜双重标记法

用９ 只成年ＳＤ 大鼠向单侧眼球玻璃体内注入假狂犬病毒３～４ μｌ,存活７２ ｈ 或９６ ｈ 后灌注、取材、Ｅｐｏｎ ８１２ 包埋,行免疫电镜胶体金标记。结果：（１）两个时间组视交叉上核内精氨酸血管加压素神经元被胶体金标记;（２）假狂犬病毒感染的视交叉上核神经元以含病毒颗粒为特征;（３）视交叉上核内少量神经元既含病毒颗粒又被精氨酸血管加压素胶体金标记。本研究结果首次证实视网膜节细胞与视交叉上核内的少数精氨酸血管加压素神经元之间有直接的突触联系,提示此类精氨酸血管加压素神经元可能直接接受来自视网膜的光信息。     

大鼠视交叉上核内VIP、AVP及SOM样神经元的相互关系──免疫组化双重反应法研究

视交叉上核具有生物钟功能已为很多实验研究所证实，但其功能机制尚在探索之中。本实验采用双重免疫组织化学反应技术对大鼠视交叉上核内ＶＩＰ、ＡＶＰ及ＳＯＭ样三大神经元群之间的相互联系进行了观察．结果表明：（１）ＶＩＰ样扣结广泛分布于ＡＶＰ样神经元周围，数量最多、密度最大；而ＳＯＭ样扣结贴附于ＶＩＰ及ＡＶＰ样神经元的数量次之；（２）ＡＶＰ样扣结与ＶＩＰ样神经元之间，ＶＩＰ样扣结与ＳＯＭ样神经元之间也形成联系．上述发现为视交叉上核功能机制的研究提供了进一步的形态学依据．