大白鼠下丘脑促肾上腺皮质激素(ACTH)样免疫反应神经元的分布及功能意义

本文应用免疫细胞化学技术观察大白鼠下丘脑促肾上腺皮质激素样神经元胞体,纤维及串珠样膨体的分布。胞体位于弓状核、下丘脑前核的腹侧、视上背侧连合、室周层的腹侧区及乳头体核腹侧。纤维及串珠样膨体广泛地分布于下丘脑,串珠样膨体在室旁核和室周层密集。串珠样膨体贴室管膜分布,伸至室管膜下神经毯,有的穿行室管膜上皮细胞之间并多与室管膜上皮细胞接触或穿过室管膜上皮细胞之间至第三脑室腔。在第三脑室侧壁的室管膜上皮细胞之间偶见促肾上腺皮质激素反应细胞。室旁核区促肾上腺皮质激素免疫反应串珠样膨体可能作用于催产素和后叶加压素神经元,控制催产素和后叶加压素的分泌和释放。室周层的串珠样膨体直接与脑脊液接触可认为是促肾上腺皮质激素神经元释放分泌产物的另一途径。     

切除两侧肾上腺对大鼠下丘脑加压素、催产素神经元的影响

为了进一步确定加压素(VP)在应激反应中的作用,我们应用免疫组化和免疫电镜观察了切除两侧肾上腺对大鼠下丘脑室旁核和视上核的神经内分泌细胞的影响,发现下丘脑室旁核VP神经元处于功能亢进状态,其合成、储存和分泌VP的功能均亢进,而视上核的加压素(VP)神经元以及室旁核和视上核的催产素(OT)神经元的功能状态均无明显改变,提示室旁核的VP神经元可能是参与下丘脑—垂体—肾上腺这一应激反应轴调节的重要因素。     

高渗刺激诱导大鼠下丘脑室旁核和视上核神经激肽B受体阳性神经元表达Fos

目的研究神经激肽Ｂ受体（ＮＫ３受体）与机体渗透压调节之间的可能关系。方法用双重免疫组织化学染色技术,高渗刺激采用静脉内注射１．５ｍｏｌ／ＬＮａＣｌ的方法,观察了下丘脑室旁核和视上核内ＮＫ３受体阳性神经元在高渗刺激下的Ｆｏｓ表达情况。结果高渗盐水可诱导下丘脑室旁核和视上核内大量神经元表达Ｆｏｓ。在室旁核,双标细胞约占ＮＫ３受体阳性神经元的８８％,约占Ｆｏｓ阳性细胞的７１％;在视上核的主部,双标细胞约占ＮＫ３受体阳性神经元的７４％,约占Ｆｏｓ阳性细胞的４３％。结论室旁核和视上核内ＮＫ３受体阳性神经元可能参与大鼠渗透压调节过程。     

电击足底对大鼠下丘脑视上核及室旁核加压素样细胞的影响

本实验用特异性兔抗精氨酸加压素血清对正常和受到不同时间电击足底刺激的雄性大鼠下丘脑组织切片作了免疫细胞化学染色,观察了视上核和室旁核内加压素样细胞的形态学变化,并以显微分光光度计和显微图象分析仪列这些细胞内加压素样物质的相对含量和细胞截面积的变化进行了研究,以期对这种应激条件下下丘脑加压素释放与否问题有一较直观的了解。结果显示,电击组与对照组相比,视上核和室旁核细胞内加压素样物质减少,细胞胞体缩小。早期下丘脑垂体束细串珠样纤维增多,后期减少。正中隆起内带加压素样纤维染色略变淡,外带内细串珠状加压素样纤维增加。视上核和室旁核某些加压素样细胞的树状突起的变化较为特殊。一些向第三脑室侧壁和脑底面神经胶质板投射的树突在电击组染色依旧很深,并出现了许多大的串珠样结构,提示这些树突有向第三脑室和蛛网膜下腔分泌加压素样物质的可能。上述结果说明电击足底刺激视上核和室旁核细胞的神经分泌机能增强,可能通过下丘脑垂体束向垂体后叶,经正中隆起外带门脉血管向垂体前叶以及通过树突向脑脊液中释放加压素样物质增加。     

含后叶加压素的视上核神经元及含P物质的中缝背核神经元至下丘脑室旁核投射的研究

用HRP逆行追踪与免疫细胞化学结合的方法,对某些投射至大鼠下丘脑室旁核的神经元的化学性质进行了研究.结果显示在视上核内存在三种标记细胞:HRP单标细胞、后叶加压素免疫反应阳性单标细胞和HRP后叶加压素双标细胞.双标细胞为大、中型椭圆形或圆形细胞,约占HRP标记细胞总数的22%.在中缝背核投射至室旁核的神经元中,部分为P物质免疫反应阳性,双标细胞为中小型梭形细胞,约占HRP标记细胞总数的20%.上述结果提示:视上核有后叶加压素能神经元、中缝背核有P物质能神经元投射到室旁核.     

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。     

免疫组化电镜观察血管加压素(Vp)在丘脑下部及神经垂体的分布

应用免疫组化电镜现察视上核、室旁核及神经垂体内Vp样物质的分布及定位。发现免疫反应阳性Vp物质主要出现在高尔基体扁平膜囊内、粗面内质网核糖体上、神经分泌粒、树突、轴突以及非对称性突触后膜内。神经垂体的无髓神经纤维及赫令氏体内显有Vp样颗粒。通过Vp样物质的分而和定位研究,本文并进行了有关Vp合成途径的探讨。     

大鼠室旁核内催产素免疫阳性细胞树突棘样结构在脱水状态下的改变

树突棘，室旁核，催产素，脱水，免疫组化，大鼠下丘脑内催产素大细胞神经分泌细胞与水盐代谢的调节有关，并伴有细胞形态的改变如细胞体积的增大及细胞膜与细胞膜间接触的增加和多突触的形成等。本文用免疫组化法发现在脱水状态下室旁核的催产素免疫阳性神经元上树突棘样结构有所增加。光镜观察并计算室旁核前大细胞亚核、内侧大细胞亚核及后大细胞亚核中含树突棘样结构的催产素神经元百分数变化，显示正常大鼠室旁核神经元树突棘样结构多位于树突干上，少数在胞体上。前大细胞亚核含树突棘样结构的细胞百分数为２１．２７％，内侧大细胞亚核为３０．２２％，后大细胞亚核为２０．２２％。轻度脱水大鼠室旁核含树突棘样结构细胞百分数显著增加（前大细胞亚核：２８．６５％，Ｐ＜０．０５；内侧大细胞亚核：３５．５３％，Ｐ＞０．０５；后大细胞亚核：３４．７８％，Ｐ＜０．０１）。细胞上树突棘样结构数也增加，其体积略为增大。重度脱水大鼠室旁核中树突棘样结构细胞百分数增加较小，仅后大细胞亚核内有显著变化（２７．１３％，Ｐ＜０．０５）。不同程度脱水组之间无显著变化。结果说明脱水可引起神经元膜结构的改变。树突棘样结构数变化是否与新突触的形成有直接关系？尚待进一步证实。     

烫伤或外伤性骨折对下丘脑神经内分泌细胞的影响——Gomori方法、免疫组化和免疫电镜观察

为了从形态学角度进一步探讨VP、OT在应激中的作用,我们利用Gomori染色、免疫组化和免疫电镜观察,发现无论是烫伤或骨折后,大鼠下丘脑室旁核VP神经元的机能状态有明显的改变,合成、储存和分泌VP的功能均亢进,而OT神经元和视上核VP、OT神经元的机能状态无明显改变。我们推测下丘脑室旁核VP神经元的反应是损伤性应激时的变化。     

含后叶加压素的视上核神经元及含P物质的中缝背核神经元至下丘脑…

用ＨＲＰ逆行追踪与免疫细胞化学结合的方法，对某些投射到大鼠下丘脑室旁核的神经元的化学性质进行了研究。结果提示，视上核有后叶加压素能神经元、中缝背核有Ｐ物质能神经元投射到室旁核。     

胎儿(36—40周)纹状体和下丘脑NPY免疫反应神经元的分布

本文用免疫细胞化学ABC法研究胎儿(36—40周)纹状体和下丘脑NPY免疫反应神经元的分布。在胎儿的纹状体发现尾状核和壳含有许多NPY免疫反应神经元的胞体和纤维。这两个区域的一些血管壁内也含有NPY免疫反应神经元的胞体和纤维。胎儿下丘脑的漏斗核和视上核含密集的NPY免疫神经元胞体,在室旁核偶尔也可见到少数免疫神经元胞体。本文首次报道了尾状核和壳的血管壁内及视上核含有NPY免疫反应神经元胞体。     

大鼠下丘脑生长抑素神经元性差别的观察

本实验用PAP免疫组织化学方法对比观察了雄性与雌性大鼠下丘脑生长抑素(SRIF)神经元胞体、纤维在正常和改变性激素代谢条件下数量或染色程度的差别。结果表明,在室周核(PV)、室旁核(PVN)和视交叉上核(SCN)内,雄性大鼠的阳性细胞和纤维较雌性多。此外,在视前内侧区(MPO)雄性有大量细丝样阳性纤维网络,而雌性只有较稀疏的阳性纤维。切除睾丸后大鼠PV、PVN、SCN阳性细胞和纤维减少,MPO和正中隆起阳性纤维密度降低。而切除卵巢的大鼠在上述区域的阳性胞体和纤维密度增强,当给去性腺的雌、雄性大鼠以同性激素替代后,染色结果接近正常。     

Vasopressin neuron survival in neonatal Brattleboro rats; critical factors in graft development and innervation of the host brain

Previously it was found that grafts of supraoptic plus paraventricular areas from 19-day-old foetal normal rats survived in the third ventricle of the brain of 4- to 6-day-old, vasopressin-deficient Brattleboro pups, but could not alleviate their polyuria. In the present series, factors important in graft development were analysed. Again using day-19 fetuses as donors, anterohypothalamus grafts as well as grafts placed near a crushed median eminence survived relatively poorly, but showed the presence of vasopressin neurons immunocytochemically one month post-grafting. Homotopic grafting in the supraoptic nucleus, however, even failed to show surviving vasopressin neurons. Graft survival was improved by the use of donor tissue of fetuses younger than day 19. Parvocellular vasopressin cells were frequently seen, organized into clusters resembling the normal suprachiasmatic nucleus. However, magnocellular neurons, as normally seen in supraoptic and paraventricular nuclei, only survived grafting when taken between days 11 and 15 of fetal age. It was concluded that only immature vasopressin neurons survived grafting under the condition employed. Magnocellular neurons had a limited fiber outgrowth into the host brain and median eminence. Most large neurons only stained with non-specific neurophysin antiserum, not with specific vasopressin-associated neurophysin antiserum. Thin fibers of the parvocellular vasopressin neurons provided only occasional and sparse innervation of the host median eminence and lateral septum (one case), but several examples of massive fiber bundles running dorsally from graft into host brain were observed. These fibers terminated in the thalamic periventricular area, a nucleus that is normally innervated by the vasopressin neurons of the suprachiasmatic nucleus.The failure of the grafts to provide adequate vasopressinergic innervation of the host median eminence probably explains why none of the nearly 200 Brattleboro neonates operated upon showed any sign of relief of their diabetes insipidus. It suggests, however, that the present procedures might be useful in restoring central vasopressinergic functions in the developing Brattleboro rat.     

后叶加压素在下丘脑的分布和释放途径及失水对正中隆起中后叶加压素的影响

我们用免疫细胞化学方法(ICC)对大白鼠下丘脑中加压素(VP)免疫反应阳性的神经元作了较详细研究。观察到VP阳性神经元存在于下丘脑室旁核(PVN)各亚核、视上核(SON)、交叉上核(SCN)、室周核(PN)及一些附属核团,包括环状核(CN)、交叉后核(RCN)、下丘脑外侧核(HLN)、穹窿周围核(PFN)。且发现一特殊的VP阳性胞体聚集区—很可能是多巴胺神经元聚集区A_(14)中的细胞,位于第三脑室侧壁中1/3段两侧,腹内侧核背侧。本文首次观察到在PVN和SON之间有VP阳性的神经纤维相联系。ICC和免疫电镜研究进一步证明在正中隆起外带存在VP阳性纤维,含大颗粒囊泡的VP末梢紧邻门脉毛细血管。将HRP注入第四脑室用HRP逆行追踪与ICC方法相结合,在PVN中观察到双标细胞,与直接用ICC法所见VP阳性轴突伸入第三脑室腔的结果一致。说明PVN中存在接触脑脊液神经元。干渴动物正中隆起的内、外带中的VP免疫反应明显减弱。     

Immunocytochemical localization of corticotropin-releasing factor in the brain of the turtle, Mauremys caspica

Brain sections of the turtle, Mauremys caspica were studied by means of an antiserum against rat corticotropin-releasing factor. Immunoreactive neurons were identified in telencephalic, diencephalic and mesencephalic areas such as the cortex, nucleus caudatus, nucleus accumbens, amygdala, subfornical organ, paraventricular nucleus, hypothalamic dorsolateral aggregation, nucleus of the paraventricular organ, infundibular nucleus, pretectal nucleus, periventricular grey, reticular formation and nucleus of the raphe. Many immunoreactive cells located near the ependyma were bipolar, having an apical dendrite that contacted the cerebrospinal fluid. Immunoreactive fibers were seen in these locations and in the lamina terminalis, lateral forebrain bundle, supraoptic nucleus, median eminence, neurohypophysis, tectum opticum, torus semicircularis and deep mesencephalic nucleus. Parvocellular bipolar immunoreactive neurons from the paraventricular and infundibular nuclei projected axons that joined the hypothalamo-hypophysial tract and reached the outer zone of median eminence, and the neural lobe of the hypophysis where immunoreactive fibers terminated close to intermediate lobe cells. From these results it can be concluded that, as in other vertebrates, corticotropin-releasing factor in the turtle may act as a releasing factor and, centrally, as a neurotransmitter or neuromodulator.     

Immunocytochemical localization of corticotropin-releasing factor in the brain of the turtle,Mauremys caspica

Brain sections of the turtle, Mauremys caspica were studied by means of an antiserum against rat corticotropin-releasing factor. Immunoreactive neurons were identified in telencephalic, diencephalic and mesencephalic areas such as the cortex, nucleus caudatus, nucleus accumbens, amygdala, subfornical organ, paraventricular nucleus, hypothalamic dorsolateral aggregation, nucleus of the paraventricular organ, infundibular nucleus, pretectal nucleus, periventricular grey, reticular formation and nucleus of the raphe. Many immunoreactive cells located near the ependyma were bipolar, having an apical dendrite that contacted the cerebrospinal fluid. Immunoreactive fibers were seen in these locations and in the lamina terminalis, lateral forebrain bundle, supraoptic nucleus, median eminence, neurohypophysis, tectum opticum, torus semicircularis and deep mesencephalic nucleus. Parvocellular bipolar immunoreactive neurons from the paraventricular and infundibular nuclei projected axons that joined the hypothalamo-hypophysial tract and reached the outer zone of median eminence, and the neural lobe of the hypophysis where immunoreactive fibers terminated close to intermediate lobe cells. From these results it can be concluded that, as in other vertebrates, corticotropin-releasing factor in the turtle may act as a releasing factor and, centrally, as a neurotransmitter or neuromodulator.     

Immunohistochemical localization of chemokine CXCL14 in rat hypothalamic neurons

We immunohistochemically investigated the distribution of CXCL14, also called BRAK protein in the rat hypothalamus using anti-human CXCL14 serum. CXCL14-immunoreactive somata were localized in the periventricular area and paraventricular and supraoptic hypothalamic nuclei. In the former, immunoreactive neuronal somata, confirmed by double staining with a neuronal marker, NeuN, contained diffuse CXCL14-like immunoreactivity in their perikarya. In contrast, immunoreactive somata in the latter contained immunoreactive puncta within their perikarya. Very dense immunoreactive fibers and puncta were seen in the median eminence. Dense immunoreactive fibers were seen in the arcuate nucleus and ventromedial hypothalamic nucleus. Other hypothalamic areas contained a few immunoreactive fibers and puncta. These results demonstrated for the first time that CXCL14 protein is present in a subset of hypothalamic neurons and suggest that CXCL14 participates in hypothalamic functions such as control of autonomic nervous systems and/or participates in immune cell recruitment via the median eminence.     

强啡肽B免疫反应阳性神经元在大鼠下丘脑的分布及与精氨酸加压素的共存

实验应用免疫细胞化学 PAP法显示了强啡肽 B免疫活性阳性神经元在大鼠下丘脑形态特征和分布特点。结果表明 :强啡肽 B正常条件下免疫活性阳性神经元仅在下丘脑的视上核、室旁核、环核、附属神经分泌核和室管膜。正中隆起处有强啡肽 B免疫活性阳性纤维分布。侧脑室注射秋水仙素后在下丘脑视前区、前区、室周核、前连合核、交叉上核、交叉后核、弓状核、背侧区、背内侧核、穹隆周核、下丘脑外侧区、腹内侧核、室周大细胞区等核区显示了强啡肽 B免疫活性阳性神经元。双标记免疫组织化学方法还显示强啡肽 B与精氨酸加压素主要共存于下丘脑室旁核 ,次为视上核 ,附属神经分泌核和下丘脑外侧区     

Mapping of somatostatin-28 (1-12) in the alpaca diencephalon

Using an immunocytochemical technique, we report for the first time the distribution of immunoreactive cell bodies and fibers containing somatostatin-28 (1-12) in the alpaca diencephalon. Somatostatin-28 (1-12)-immunoreactive cell bodies were only observed in the hypothalamus (lateral hypothalamic area, arcuate nucleus and ventromedial hypothalamic nucleus). However, immunoreactive fibers were widely distributed throughout the thalamus and hypothalamus. A high density of such fibers was observed in the central medial thalamic nucleus, laterodorsal thalamic nucleus, lateral habenular nucleus, mediodorsal thalamic nucleus, paraventricular thalamic nucleus, reuniens thalamic nucleus, rhomboid thalamic nucleus, subparafascicular thalamic nucleus, anterior hypothalamic area, arcuate nucleus, dorsal hypothalamic area, around the fornix, lateral hypothalamic area, lateral mammilary nucleus, posterior hypothalamic nucleus, paraventricular hypothalamic nucleus, suprachiasmatic nucleus, supraoptic hypothalamic nucleus, and in the ventromedial hypothalamic nucleus. The widespread distribution of somatostatin-28 (1-12) in the thalamus and hypothalamus of the alpaca suggests that the neuropeptide could be involved in many physiological actions.