大鼠下丘脑内的一氧化氮合酶与雌激素受体双标神经元

目的:探讨一氧化氮合酶(NOS)和雌激素受体(ER)在下丘脑诸核团的分布及共存,为揭示雌激素与一氧化氮之间的内在联系提供形态学依据。方法:采用NADPH-d组织化学法并结合免疫组织化学技术,观察雌性大鼠下丘脑内NOS阳性神经元、ER阳性神经元以及NOS/ER双染神经元的形态及分布。结果:NOS阳性神经元主要分布在下丘脑室旁核、视上核、下丘脑外侧区和室周核;ER阳性神经元在下丘脑诸核团的表达不及NOS阳性神经元广泛;NOS与ER双染神经元主要分布在下丘脑的室旁核、视上核、下丘脑外侧区及室周核;其他区域可见散在分布的双染神经元。结论:NOS与ER双染神经元主要集中分布在视上核的背内侧和背外侧部及室旁核小细胞部腹内侧区,在下丘脑外侧区分布较广但比较分散,室周核呈散在分布。     

大鼠下丘脑室旁核中一氧化氮合酶阳性神经元的生后发育

本文用NADPH－d组织化学方法观察NOS阳性神经元在大鼠下丘脑室旁核生后发育各阶段（1、7、14、21、28和90d）的形态及分布特征。结果显示，1d时下丘脑室旁核内已有密集的NOS阳性神经元分布，但随生长发育，室旁核的截面积逐渐变大，其中的NOS神经元主要集中在该核的外侧大细胞部以及腹侧部，单位面积中的NOS神经元的密度逐渐降低。到21d，下丘脑室旁核NOS阳性神经元的分布密度较1d时下降50％。28d以后至成年鼠（90d），此密度维持在一定水平．提示下丘脑室旁核中NOS神经元的生后发育主要在生后1d至21d之间，并提示胚胎时期该核中已有NOS神经元存在。     

束缚应激大鼠下丘脑内一氧化氮合酶与c-fos蛋白的共存

为了探讨下丘脑内一氧化氮与应激之间的关系，本实验应用NADPH-d组化法和C-fos免疫组化技术相结合的方法，对束缚应激大鼠下丘脑内一氧化氮合酶（NOS）和c-fos蛋白的分布以及两者的共存关系进行了观察。结果表明，大鼠在束缚应激4h后，（1）室旁核大细胞部和视上核可见密集深染的NOS阳性大细胞；（2）室旁核小细胞部、背内侧核、穹窿周核、环状核、腹内侧核腹外侧部、结节内侧核、外侧区、室周区、乳头体前核和内侧核的外侧区等核团出现疏密不等和深浅不一的NOS阳性细胞；（3）C-fos蛋白以室旁核表达最为强烈，视前区、背内侧核、弓状核和外侧区亦有较强的表达；（4）在外侧区、室旁核小细胞部及其附近的室周区、背内侧核及乳头体前核腹侧部约有10％～15％的中、小型NOS阳性细胞同时表达C-fos蛋白，室旁核大细胞部则仅有较少的NOS阳性大细胞表达C－fos蛋白，在结节区、结节内侧核和视上核视交叉后部则偶见双标细胞。结果提示上述下丘脑核团内的部分一氧化氮能神经元与束缚应激反应有关。     

大鼠下丘脑一氧化氮合酶（NOS）阳性神经元的分布

观察大鼠下丘脑各核团NOS阳性神经元的分布。采用还原型尼克酰胺腺嘌呤二核苷酸脱氢酶（NADPH－d）法，结果显示，大量NOS阳性神经元见于下丘脑外侧区、视上核（SO）和室旁核（Pa）；出现较多NOS阳性神经元的部位是视前大细胞核，见到少量NOS阳性神经元的部位是室周核、视前内侧区、视前外侧区和下丘脑前区。结论：NOS阳性神经元分布于下丘脑的许多核团。     

内脏伤害性刺激后Fos在大鼠脑内NOS阳性神经元内的表达

目的：观察一氧化氮合酶(NOS)阳性神经元在内脏伤害性信息传递通路上的分布。方法：给予大鼠内脏伤害性刺激后，采用Fos免疫组织化学(ABC法)和还原型尼克酰胺腺嘌呤二核苷酸脱氢酶(NADPH-d)组织化学双重染色的方法，观察脑内NOS和Fos阳性神经元的分布。结果：脑内Fos／NOS双标阳性神经元主要分布在孤束核，中缝背核，丘脑室旁核，下丘脑室旁核、室周核、背内侧核，中脑导水管周围灰质腹外侧部、背外侧部，臂旁内侧核，内侧缰核，杏仁复合体内侧部等部位。结论：NO是内脏伤害性信息传递和调控通路上的神经递质之一。     

下丘脑室旁核经迷走神经复合体对哮喘大鼠的神经调控研究

为探讨下丘脑室旁核对哮喘大鼠的神经调控途径,取健康雄性SD大鼠制备哮喘模型并诱发哮喘发作,运用WGA-HRP逆行追踪法与免疫组织化学染色法(ABC法)相结合的双重标记方法,在光镜下观察向迷走神经复合体(DVC)发出投射的下丘脑室旁核(PVN)神经元内Fos蛋白的表达情况。结果显示:PVN内有三种阳性细胞,即HRP逆行标记神经元、Fos样免疫阳性神经元和HRP/Fos双标神经元。这些神经元主要见于PVN小细胞部的内侧亚核和外侧亚核,散在分布于背侧亚核,在前小细胞亚核内未见阳性反应;Fos样免疫阳性细胞呈双侧分布,且HRP逆标神经元,HRP/Fos双标神经元也为双侧分布,但以注射区同侧占优势。HRP/Fos双标神经元占HRP标记细胞的44.22%。本研究结果提示,哮喘大鼠发作时中枢内包括下丘脑PVN、延髓DVC的多个脑区内神经元兴奋,且两者之间通过直接投射联系参与哮喘的调控。     

大鼠垂体后叶中神经降压素阳性神经纤维的起源

向垂体后叶注射WGA-HRP,进行逆行追踪并与免疫组织化学相结合研究了大鼠垂体后叶中神经降压素(NT)能神经纤维的起源。投射到垂体后叶的NT免疫阳性神经元胞体主要位于下丘脑室旁核小细胞部、室周区,环状核、室旁核大细胞亚核内侧部、视上核背侧部、穹窿后核及下丘脑前区、外侧区。弓状核内未见任何双标记神经元,从而否定了Goedert等用损毁的方法得出的大鼠垂体后叶中NT阳性神经纤维起源于弓状核的结论。一些室周双标记神经元位于室管膜内,距第三脑室腔很近,常挤在室管膜细胞之间。提示这些神元在监测脑脊液的化学变化,调节垂体后叶分泌方面起一定的作用。     

大鼠脑内星形胶质细胞对渗透压改变的反应及其和神经元的相互关系

为观察大鼠在饮用 3 % Na Cl溶液 2 d和 5 d时的脑内星形胶质细胞的反应变化及相互关系。本文应用免疫组织化学三重标记法 ,在脑原位切片同时显示 FOS、胶质原纤维酸性蛋白、酪氨酸羟化酶 (或加压素 )的表达、相互关系及分布规律。结果显示 :(1)实验组大鼠脑内孤束核、味觉核、臂旁核、蓝斑、导水管周围灰质的腹外侧区、上丘中灰层、下丘脑室旁核外侧大细胞部、视上核、和穹隆下器同时出现 FOS阳性神经元胞核和胶质原纤维酸性蛋白阳性星形胶质细胞。 (2 )在孤束核、蓝斑、下丘脑室旁核外侧大细胞部和视上核出现酪氨酸羟化酶阳性神经元 ,在下丘脑室旁核外侧大细胞部、下丘脑室旁核腹侧部和视上核等出现加压素阳性神经元。(3 )在孤束核、蓝斑、或下丘脑室旁核外侧大细胞部、视上核的三重免疫组化染色切片上见到胶质原纤维酸性蛋白阳性星形胶质细胞包绕 FOS阳性和酪氨酸羟化酶阳性 (或加压素阳性 )神经元 ,形成复合体。提示 :脑内相关核团内的星形胶质细胞与神经元共同参与对渗透压的调节 ,并以神经元—星形胶质细胞复合体作为功能单位     

小鼠下丘脑室旁核的亚区

综合运用Nissl染色,HRP逆行标记,Gomori染色,加压素、催产素免疫细胞化学和生物图象参数测量等方法对小鼠下丘脑室旁核的细胞组成及分布特点进行分析。结果表明小鼠室旁核除大细胞神经元和小细胞神经元外还有数量较多的中等神经元。三者混杂分布。该核团前、后部,内、外侧,及外侧的腹、背部其细胞密度,含催产素、加压素的神经分泌细胞的分布特点以及投射联系等均有差异。依据这些特点,小鼠下丘脑室旁核可分为五个亚区:前亚区(PVA);内侧亚区(PVM);背外侧亚区(PVLd);腹外侧亚区(PVLv),后亚区(PVLp)。     

大鼠下丘脑室旁核和视上核内神经激肽B受体和加压素的共存研究

目的研究神经激肽Ｂ受体（ＮＫ３受体）免疫反应产物在大鼠下丘脑室旁核和视上核的分布及其与加压素的共存。方法免疫组织化学染色,标本在光镜和电镜下观察。共存研究采用相邻切片染色法。结果致密的ＮＫ３受体阳性产物分布于室旁核的后大细胞部和视上核的主部。免疫电镜观察发现ＮＫ３受体阳性反应产物出现于室旁核和视上核的胞体和树突内。在相邻切片上观察到室旁核和视上核内有相当数量的ＮＫ３受体阳性神经元,同时含有加压素,它们主要分布于室旁核的后大细胞部和视上核的主部。结论根据本研究和以往的机能学的研究结果,推测下丘脑室旁核和视上核内的ＮＫ３受体阳性神经元可能参与调控机体内环境改变时下丘脑加压素的释放。     

Intermittent activation of peripheral chemoreceptors in awake rats induces Fos expression in rostral ventrolateral medulla-projecting neurons in the paraventricular nucleus of the hypothalamus

Despite the well-established sympathoexcitation evoked by chemoreflex activation, the specific sub-regions of the CNS underlying such sympathetic responses remain to be fully characterized. In the present study we examined the effects of intermittent chemoreflex activation in awake rats on Fos-immunoreactivity (Fos-ir) in various subnuclei of the paraventricular nucleus of the hypothalamus (PVN), as well as in identified neurosecretory preautonomic PVN neurons. In response to intermittent chemoreflex activation, a significant increase in the number of Fos-ir cells was found in autonomic-related PVN subnuclei, including the posterior parvocellular, ventromedial parvocellular and dorsal-cap, but not in the neurosecretory magnocellular-containing lateral magnocellular subnucleus. No changes in Fos-ir following chemoreflex activation were observed in the anterior PVN subnucleus. Experiments combining Fos immunohistochemistry and neuronal tract tracing techniques showed a significant increase in Fos-ir in rostral ventrolateral medulla (RVLM)-projecting (PVN-RVLM), but not in nucleus of solitarii tract (NTS)-projecting PVN neurons. In summary, our results support the involvement of the PVN in the central neuronal circuitry activated in response to chemoreflex activation, and indicate that PVN-RVLM neurons constitute a neuronal substrate contributing to the sympathoexcitatory component of the chemoreflex.     

大鼠下丘脑室旁核对脾脏免疫功能神经调控的研究

目的 探讨PVN不同亚核在调控脾脏免疫功能中的作用。方法 4只SD大鼠脾脏内注射假狂犬病毒（PRV）96h后,采用免疫组化法和体视学方法研究被假犬病毒跨突触感染的神经元在PVN不同亚核内的分布特点及其与PVN内AVP神经元位置配布间的相互关系。结果 PRV感染的神经元主要聚集于PVN段的尾侧大细胞亚核（ＰＭ）和外侧小细胞亚核（LP）（占总面积的73.49%),少量分布于喙段的前小细胞亚核（LP）、中段的背侧小细胞亚核（DP）和室周小细胞亚核内（PP）。其中LP及PM内的部分PRV感染神经元分布在AVP阳性神经元聚集的区域内。结论 PVN对脾脏免疫功能的调控除了传统神经内分泌途径外,还可能存在下列途径：PM内的AVP阳性神经元和LP、DP及AP内的神经元通过向延髓背侧及脊髓中间外侧柱的投射,然后再通过副交感和交感神经的直接神经支配途径调控脾脏的功能。     

大鼠下丘脑室旁核内一氧化氮合酶神经元的生后发育

应用 NADPH-黄递酶组织化学和一氧化氮合酶 (NOS)免疫组织化学方法以及计算机图像分析 ,观察 NOS神经元在大鼠下丘脑室旁核 (PVN)生后发育各阶段的形态及分布特征。结果显示 ,1d时 PVN内已有 NOS神经元。随着生长发育 ,PVN的面积逐渐变化 ,NOS神经元主要集中在 PVN的外侧大细胞部及腹侧部 ,细胞逐渐增多 ,胞体的平均截面积逐渐变大 ,平均灰度值逐渐降低。14d以后至成年鼠 (90 d)以上变化不明显。结果提示 ,PVN中 NOS神经元的生后发育和成熟主要在 14d前 ,尤以 7d至 14d为关键时期     

Coexistence of glucocorticoid receptor-like immunoreactivity with neuropeptides in the hypothalamic paraventricular nucleus

Summary The paraventricular nucleus (PVN) of male albino rats was analyzed for the presence of glucocorticoid receptor-like immunoreactivity (GR-LI) in neuropeptide containing neurons. Using immunohistochemistry, coronal sections trough the entire PVN were double-stained with a mouse monoclonal antibody against GR and one of the following antisera: rabbit antiserum to corticotropin releasing factor (CRF), neurotensin (NT), enkephalin (ENK), cholecystokinin (CCK), thyrotropin releasing hormone (TRH), galanin (GAL), peptide histidine isoleucine (PHI), vasoactive intestinal polypeptide (VIP), somatostatin (SOM) or tyrosine hydroxylase (TH). For comparison the occurrence of GR-LI in NT-, SOM-, NPY- or TH-positive neurons of the arcuate nucleus was also studied. Our results indicate that GR-LI is present in the parvocellular part of the PVN but not in its magnocellular portion. Virtually every parvocellular neuron in the PVN containing one of the above mentioned peptides was also positive for GR, with the exception of SOM neurons, of which only about two thirds showed detectable levels of GR-LI. All TH-positive, presumably dopamine neurons in the PVN were GR-positive. In the arcuate nucleus all TH- and NPY-positive neurons as well as a large proportion of the SOM- and NT-immunoreactive neurons contained GR-LI. The results indicate that in the PVN, in addition to the CRF neurons, certain peptidergic neurons in the parvocellular part of the PVN, without any established role in the control of ACTH synthesis and release, may also be under glucocorticoid control. This seems to be the case also for most arcuate neurons.     

Anatomical interactions between the central amygdaloid nucleus and the hypothalamic paraventricular nucleus of the rat: a dual tract-tracing analysis

Axonal connections between the amygdala and the hypothalamic paraventricular nucleus were examined by combined anterograde-retrograde tract tracing. Iontophoretic injections of the retrograde tracer Fluorogold were placed in the paraventricular nucleus, and the anterograde tracer PHA-L in the ipsilateral central or medial amygdaloid nuclei. Single and double-label immunohistochemistry were used to detect tracers. Single label anterograde and retrograde tracing suggest limited evidence for direct connections between the central or medial amygdala and the paraventricular nucleus. In general, scattered PHA-L-positive terminals were seen in autonomic subdivisions of the paraventricular nucleus (lateral parvocellular, dorsal parvocellular and ventral medial parvocellular subnuclei) following central or medial amygdaloid nulcleus injection. Double-label studies indicate that central and medial amygdaloid nucleus efferents contact paraventricular nucleus -projecting cells in several forebrain nuclei. In the case of central nucleus injections, PHA-L positive fibers occasionally contacted Fluorogold-labeled neurons in the anteromedial, ventromedial and preoptic subnuclei of the bed nucleus of the stria terminalis. Overall, such contacts were quite rare, and did not occur in the bed nucleus of the stria terminalis regions showing greatest innervation by the central amygdaloid nucleus. In contrast, medial amygdala injections resulted in a significantly greater overlap of PHA-L labeling and Fluorogold-labeled neurons, with axosomatic appositions observed in medial divisions of the bed nucleus of the stria terminalis, anterior hypothalamic area and preoptic area. The results provide anatomical evidence that a substantial proportion of amygdaloid connections with hypophysiotrophic paraventricular nucleus neurons are likely multisynaptic, relaying in different subregions of the bed nucleus of the stria terminalis and hypothalamus.     

Effects of hyperosmotic stimulation and adrenalectomy on vasopressin mRNA levels in the paraventricular and supraoptic nuclei of the hypothalamus: in situ hybridization histochemical analysis using a synthetic oligonucleotide probe

The effects of salt loading and adrenalectomy on arginine vasopressin (AVP) mRNA levels in the paraventricular nucleus (PVN) and the supraoptic nucleus (SON) of the hypothalamus were studied by semiquantitative in situ hybridization histochemistry, using a synthetic oligonucleotide probe and a computer-assisted image analysis system. Salt loading (2% NaCl) for 7 days produced marked increases in AVP mRNA levels in the magnocellular neurons of the PVN, SON, and accessory nuclei. Adrenalectomy caused an increase in AVP mRNA expression in the magnocellular part of the PVN and the expansion of hybridization signals into its medial parvocellular region, where the cell bodies of corticotropin-releasing hormone (CRH) neurons are located. No apparent alteration of AVP mRNA levels was observed in the SON following adrenalectomy. These results indicate that hyperosmotic stimulation and the loss of circulating glucocorticoids had differential effects on AVP gene expression in the PVN and SON, and that the magnocellular PVN and SON neurons responded in different manners to the loss of feedback signals.     

Identification and distribution of the spinal and hypophyseal projection neurons in the paraventricular nucleus of the rat. A light and electron microscopic study with the horseradish peroxidase method

Summary The distribution of labeled neurons in the paraventricular nucleus of the hypothalamus (PVN) was studied following injections of horseradish peroxidase (HRP) into the spinal cord (C8 to T1) or the hypophysis in the rat. Injections were also made in the spinal cord in another group of animals, which were subjected to water deprivation for a period of 3 days, and the PVN of these animals was examined with the electron microscope.Spinal projection neurons (paraventriculospinal tract, PVST, neurons) formed two groups; the dorsal and the ventral groups. They were located within the parvocellular part of the PVN and fused into one at the caudal level. The neurons of the dorsal group were well assembled whereas those of the ventral group were intermingled with paraventriculohypophyseal tract (PVHT) neurons, which were concentrated in the magnocellular part. Electron microscopic observations revealed that HRP-labeled neurons after spinal injections did not contain neurosecretory granules and that they were not affected by water deprivation. On the other hand, neurons containing a number of neurosecretory granules displayed a significant degree of dilatation of the endoplasmic reticulum as the result of water deprivation. These neurons contained no HRP granules.The present findings suggest that the PVST neurons are distinct from the PVHT neurons and that the neuronal groups of both systems form different cell columns within the nucleus.Abbreviations C caudal - D dorsal - Mgc magnocellular part - NH neurohypophysis - PVHT paraventriculohypophyseal tract - PVN paraventricular nucleus - PVST paraventriculospinal tract - R rostral - SC spinal cord - V ventral - III third ventricle     

加压素能和宫缩素能神经元在新生儿下丘脑的分布

本文用ABC法对加压素样和宫缩素样神经元在新生儿下丘脑的分布进行了观察。结果发现,两者的神经元集中分布于视上核、室旁核及副大细胞分泌核。根据两者的分布特点,又将视上核、室旁核和副大细胞分泌核再分为若干分区,各分区均以加压素样神经元为主,约占总数的80～90％。本文结果提示加压素样和宫缩素样神经元在下丘脑的分布具有动物种属和年龄特征。