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。     

新生期大白鼠皮下注射谷氨酸单钠对成年后下丘脑α-促黑素细胞激素神经元免疫反应性的影响

本文用免疫组化方法研究了新生期大白鼠注射谷氨酸单钠(MSG)对成年后下丘脑α-促黑素细胞激素(α-MSH)免疫反应神经元的影响,结果显示MSG处理以后下丘脑弓状核区α-MSII免疫反应神经元减少甚至完全消失,但不影响下丘脑背外侧区的α-MSH神经元群。文中还讨论了这两群α-MSH神经元的生理作用。     

电刺激腹中隔区对兔视前区前下丘脑温敏神经元放电的影响

目的和方法:采用玻璃微电极细胞外引导单位神经元放电的方法,观察电刺激兔腹中隔区(VSA)时,视前区-下丘脑前部(POAH)温度敏感神经元放电频率的变化。结果:电刺激腹中隔区可使视前区-下丘脑前部热敏神经元放电频率增加,冷敏神经元放电频率减少。结论:腹中隔区可能通过影响视前区-下丘脑前部温敏神经元放电频率而参与体温调节。     

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。     

雌性大鼠去卵巢后下丘脑CREB阳性神经元的形态学变化

目的：观察雌性大鼠去卵巢后，下丘脑视前区(PA)内转录因子环磷酸腺苷反应元件结合蛋白(CREB)阳性神经元的变化，及探讨CREB与GnRH分泌变化的关系。方法：采用免疫细胞化学方法对下丘脑视前内侧区(MPA)和视前外侧区(LPA)内CREB阳性神经元进行形态观察和细胞计数，采用图像分析系统测定CREB阳性神经元内的免疫产物的平均光密度(AOD)值。结果：(1)大量CREB阳性神经元见于对照大鼠的LPA和MPA。(2)去卵巢后CREB阳性神经元的数目和AOD值显著增高。(3)在阳性神经元分布和阳性产物的含量上有时间和亚区差异。结论：大鼠去卵巢后，在较长时间内，下丘脑CREB阳性神经元仍保持比对照组大鼠较多的数目。     

新生大鼠下丘脑多巴胺能神经元的体外发育

为了探讨下丘脑多巴胺能神经元 发育特性，取新一大鼠下丘脑神经元进行分散培养。用酷氨酸羟化酶抗血清和免疫细胞化学ＡＢＣ法显示ＤＡ能神经元，并进行图像分析。     

大鼠下丘脑内Calbindin-D28K和NADPH-d的共存

应用免疫细胞化学方法结合NADPH－d组织化学技术对大鼠下丘脑内calbindin－D28K和NADPH－d的共存进行了实验研究。结果发现：在视上核、下丘脑室旁核大细胞部可见到较多的calbindin－D28K／NADPH－d双重反应阳性神经元．这些神经元分别占以上两核团神经元总数的52．8％和42．5％；而在下丘脑的其它部位如下丘脑外侧区、下丘脑腹内侧核、穹隆周核和内侧视前区等处也可见到少量的双重反应神经元、本文的研究结果表明calbindin－D28K和NADPH－d共存于下丘脑的单个神经元内。     

大鼠垂体后叶Ang-Ⅱ阳性神经纤维的起源

用逆行追踪与免疫组织化学相结合的一种方法,证明大鼠垂体后叶中的Ang-Ⅱ能神经纤维主要起源于后大细胞室旁核的前腹侧部和背外侧部,视上核背侧部及环状核;少量双标记细胞出现在室周区和下丘脑前内侧区。这些双标记神经元的分布与加压素能神经元在下丘脑中的分布一致。     

睫状神经营养因子对应激大鼠下丘脑、垂体精氨酸加压素含量的影响

目的：研究睫状神经营养因子（ＣＮＴＦ）对应激大鼠下丘脑、垂体精氨酸加压素（ＡＶＰ）含量及下丘脑ＡＶＰ阳性神经元的影响。方法：选用条件性足底电击应激大鼠模型，用放射免疫分析的方法观察双侧海马微量注射ＣＮＴＦ对应激大 下丘脑及垂体ＡＶＰ含量的影响，用免疫组织化学染色的方法结合光镜与图像分析观察下丘脑室旁核ＡＶＰ阳性神经元的变化。结果：应激大鼠下丘脑、垂体ＡＶＰ含量升高；下丘脑室旁核ＡＶＰ阳性神经元增多，染色变深，平均吸光度显著增加。给予ＣＮＴＦ的大鼠下丘脑、垂体ＡＶＰ含量明显降低；下丘脑室旁核ＡＶＰ阳性神经元减少，染色变浅，平均吸光度明显减少。结论：ＣＮＴＦ明显降低应激引起的下丘脑、垂体ＡＶＰ含量的升高。     

大鼠下丘脑内侧区生长抑素神经元的生后发育

实验应用丙烯醛浸泡固定，ＰＡＰ免疫组化方法，对生后０－３０天大鼠下丘脑内侧区背，腹内侧核生长抑素（ｓｏｍａｔｏｓｔａｔｉｎ，ＳＳ）神经元的生后发育进行了观察。结果表明新生大鼠下丘脑背，腹内侧核ＳＳ神经元形态发育为成熟。生后阶段ＳＳ神经元数量呈增多趋势。二周达高峰，背内侧核ＳＳ神经元染色明显变浅。三周腹内侧核大多数ＳＳ神经元消失，仅见少数阳性神经元散在分布。但在背内侧核内仍可见到浅染的ＳＳ神经元胞体     

Direct neural connection from the medial preoptic area to the hypothalamic arcuate nucleus of the rat

Summary Direct neural connections from the medial preoptic area (MPOA) to the arcuate nucleus were studied on light and electron microscope level by a multistep experimental procedure. The hypothalamic deafferentation technique of Halász and Pupp (1965) was used in itself or was combined with electrolytic lesions. In order to eliminate all fibers of more rostral source traversing the medial preoptic area an extended rostral preoptic deafferentation was made, and a survival time of at least 3 weeks was chosen to allow for the complete disappearance of the degenerated fragments from the arcuate nucleus. In the main experimental group the medial preoptic area was destroyed by an electrolytic lesion 3 or more weeks following such rostral preoptic deafferentations. In these animals degenerated fibers and terminals certainly of preoptic origin were found distributed bilaterally, with a predominance on the side of the lesion. — These data suggest that axons originating from medial preoptic neurons terminate in the arcuate nucleus, thus constituting a preoptico-tuberal pathway.     

雄性大鼠去势后下丘脑NOS神经元的分布

目的：探讨雄性大鼠去势术后下丘脑内一氧化氮合酶（NOS）阳性神经元的改变。方法：发育期雄性SD大鼠,分三组：假手术组,去势组和去势＋睾酮替代治疗组,利用黄递酶组织化学染色方法观察与比较各组大鼠与生殖相关各下丘脑核团内NOS神经元数目与密度,结果：在下丘脑的视前内侧核,视前室周核,正中隆起,弓状核均可见到NOS阳性标记细胞。去势术后视前内侧核内NOS神经元数目及密度降低,睾酮替代治疗可逆转,结论：一氧化氮在雄激素对下丘脑的反馈调节中起重要的介导作用。     

动脉粥样硬化大鼠弓状核内β－内啡肽免疫反应阳性细胞的变化

用免疫细胞化学ＰＡＰ法和计算机图象分析技术，对动脉粥样硬化大鼠下丘脑弓状核β－内啡肽免疫反应阳性细胞的变化进行半定量研究。结果发现；动脉粥样硬化大鼠的下丘脑弓状核内β－ＥＮＤ阳性细胞数量增加，实验组和对照组在单位剖面弓状核内，阳性细胞数分别为２９．１±５．１和１５．５±４．２个。计算机图象分析其阳性细胞的积分光密度，实验组和对照组分别为０．１１４４６±０．０５１３和０．０８３３０±０．０４１６，经统计学处理，两组之间阳性细胞和ＩＯＤ都具有显著差异（Ｐ＜０．０５）。本文提示：下丘脑弓状核内β－ＥＮＤ样阳性神经元对动脉粥样硬化的形成和／或调控过程可能有一定影响。     

GABAergic and catecholaminergic innervation of mediobasal hypothalamic beta-endorphin cells projecting to the medial preoptic area.

In the absence of cellular estrogen receptors or proven direct estrogen action in the rat, it is assumed that estrogen indirectly regulates the secretory activity of the preoptic area luteinizing hormone-releasing hormone-producing cells. We have previously shown that pro-opiomelanocortin neurons in the arcuate nucleus of the rat send axons rostrally to connect with luteinizing hormone-releasing hormone neurons of the preoptic area. An experiment combining retrograde tracing and double-immunostaining was used to test the hypothesis that rat GABAergic and/or catecholaminergic neurons can influence luteinizing hormone-releasing hormone-producing cells via mediobasal hypothalamic beta-endorphin neurons. The retrograde tracer horseradish peroxidase was injected into the medial preoptic area; two days later, arcuate nucleus Vibratome sections were double-immunostained for beta-endorphin and glutamate decarboxylase or tyrosine hydroxylase. Light and electron microscopic analysis of these triple-labeled sections demonstrated that a population of beta-endorphin-immunoreactive neurons concentrated in the ventromedial arcuate nucleus contain retrogradely transported horseradish peroxidase granules and form synaptic contacts with glutamate decarboxylase- and tyrosine hydroxylase-immunoreactive axon terminals. The present data suggest that arcuate nucleus GABA and catecholamine fibers may influence luteinizing hormone-releasing hormone-containing neurons via projective pro-opiomelanocortin cells.     

高脂血症大鼠弓状核超微结构及神经肽Y神经元的变化

目的:观察高脂血症大鼠弓状核超微结构及神经肽Y(neuropeptide Y,NPY)免疫阳性神经元的变化。方法:实验组大鼠高脂饲料饲养6周测血脂,透射电镜观察弓状核超微结构,免疫组化染色观察测量NPY免疫阳性神经元光密度、数量及截面积。结果:实验组血清总胆固醇及低密度脂蛋白胆固醇明显升高;弓状核超微结构出现明显病理学改变。NPY神经元平均光密度、细胞数、截面积减少。结论:高脂血症可诱导弓状核神经元超微结构和NPY神经元改变,为进一步探讨血脂代谢异常与中枢神经的内分泌关系提供形态学依据。     

Multiple connections of medial hypothalamic neurons in the rat

Summary The responses of 700 single neurons in the hypothalamus to electrical stimulation of the preoptic area, limbic structures, and midbrain were studied to determine the location of neurons with multiple inputs and to identify by antidromic activation the projection areas of those neurons.Converging excitatory inputs, observed in 134 responsive hypothalamic neurons, were principally derived from the preoptic, limbic, and midbrain areas. Inputs from separate nuclei of the amygdala were noted in the response of individual hypothalamic neurons. Two classes of short latency transsynaptic responses to amygdala stimulation were defined, indicating either separate pathways from the amygdala to the medial hypothalamus or two types of fibers conducting at different velocities. Stimulation of single or multiple sites in the preoptic and limbic areas, as well as in the arcuate nucleus and medial forebrain bundle produced inhibition of hypothalamic neuronal activity.Most antidromically identified medial hypothalamic neurons projected to the preoptic area, median eminence (tuberoinfundibular neurons), or midbrain. Evidence is presented for collateral projections of tuberoinfundibular neurons to the preoptic area and reticular formation. Medial hypothalamic neurons received inputs from the preoptic area, lateral septal nucleus, amygdala, ventral hippocampus (subiculum), and fornix. These findings illustrate a pattern of reciprocal connections between the medial hypothalamus and limbic and midbrain structures.It was concluded that the hypothalamus contains a type of neuron that is equipped to perform complex integrations and to coordinate directly the behavior of neurons in a diversity of anatomical regions.Abbreviations ABL basolateral nucleus of the amygdala - ACO cotical nucleus of the amygdala - AHA anterior area of the hypothalamus - ARH arcuate nucleus of the hypothalamus - DMH dorsomedial nucleus of the hypothalamus - FX fornix - HPC ventral hippocampus (subiculum) - LS lateral septal nucleus - ME median eminence - MH medial hypothalamus - MFB medial forebrain bundle - MP posterior mamillary nucleus - PH posterior nucleus of the hypothalamus - PMD dorsal premamillary nucleus - PMV ventral premamillary nucleus - POA preoptic area - PVG periventricular gray - PVH paraventricular nucleus of the hypothalamus - RF reticular formation of the mesencephalon - RT reticular nucleus of the thalamus - SUM supramamillary nucleus - VMH ventromedial nucleus of the hypothalamus Performed with financial support from the National Institutes of Health (Grants NS 09688 and RR 00165)     

Neurons containing messenger RNA encoding glutamate decarboxylase in rat hypothalamus demonstrated by in situ hybridization, with special emphasis on cell groups in medial preoptic area, anterior hypothalamic area and dorsomedial hypothalamic nucleus

Previous deafferentation studies have suggested that most hypothalamic GABAergic innervation originates from neurons within the hypothalamus. We have investigated the distribution of GABAergic cell groups in the rat hypothalamus by means of the in situ hybridization technique, using a cDNA probe for messenger RNA encoding glutamate decarboxylase. Several major GABAergic cell groups were demonstrated, including cells of the tuberomammillary nucleus, arcuate nucleus, suprachiasmatic nucleus, medial preoptic area, anterior hypothalamic area, the dorsomedial hypothalamic nucleus, perifornical area, and lateral hypothalamic area. The most prominent glutamate decarboxylase mRNA-containing cell groups were located in the medial preoptic area, anterior hypothalamic area and dorsomedial hypothalamic nucleus, and were composed of small- to medium-sized neurons. Compared to previously well-characterized GABAergic cell groups in the tuberomammillary nucleus, reticular thalamic nucleus, and non-pyramidal cells of cerebral cortex, the cells of these GABAergic groups demonstrated only weak cDNA labelling, indicating that they contain lower levels of glutamate decarboxylase mRNA. Several types of control experiments supported the specificity of this cDNA labelling, and the GABAergic nature of these cell populations was further supported by detection of glutamate decarboxylase and GABA immunoreactivity. Abundance of GABAergic cells in many hypothalamic nuclei indicates that GABA represents quantitatively the most important transmitter of hypothalamic neurons, and may be involved in neuroendocrine and autonomic regulatory functions.     

Neuroanatomical distribution of the melanocortin-4 receptors in male and female rodent brain

The melanocortin-4 receptor (MC4-R) plays a critical role in several physiological functions, from food intake, energy homeostasis, neuroendocrine and cardiovascular function, to sexual responses. The brain regions and the central neuronal pathways mediating the different actions of MC4-R remain largely unknown. We aimed to use immunocytochemistry using a specific antibody against rat MC4-R, to establish the detailed neuroanatomical distribution of MC4-R in brain slices of male and estrous female rats. We demonstrated that MC4-R-positive neurons were widely distributed in several brain regions including the cortex, thalamus, hypothalamus, and brainstem. In both male and female brains, MC4-R-positive cells were especially abundant in the hypothalamus, including the paraventricular hypothalamic nucleus, lateral septal nucleus, arcuate nucleus, supraoptic nucleus, medial preoptic area and lateral hypothalamic area. A moderate number of MC4-R-positive neurons were found in the piriform cortex, bed nucleus of the stria terminalis, medial and basolateral nuclei of amygdala, periaqueductal gray, red nucleus and raphe nucleus. A dimorphic sexual difference in the number of MC4-R-positive neurons was observed in some brain regions. In the medial preoptic area and arcuate nucleus, MC4-R-positive neurons were significantly more abundant in female than in males, whereas in the lateral hypothalamus the opposite proportion was observed. This is the first time the neuroanatomical distribution, and sex differences, of brain MC4-R localisation have been described. The distribution of MC4-R is consistent with the proposed roles of MC4-R-positive neurons and provides further information about the circuitry controlling food intake, energy balance and sexual responses in both males and females.     

Effect of electrical stimulation on the fluorescence intensity of catecholamine-containing tuberal nerve cells

1. By means of a microfluorimetric technique, the intensity of the catecholamine fluorescence was measured in nerve cells of the arcuate and periventricular hypothalamic nuclei of ovariectomized rats pre-treated with oestrogen and progesterone. In such animals the fluorescence intensity is in the range of the lowest intensities that were observed during the oestrous cycle.2. Unilateral intermittent electrical stimulation of the arcuate nucleus or of the medial preoptic area induced an acute increase of the fluorescence intensity in the cell bodies of the tuberal catecholamine-containing nerve cell group. The change was already manifest 5 min after the onset of stimulation and within 10 min the mean fluorescence intensity reached levels that are among the highest so far observed in this cell group. Prolonged stimulation of the medial preoptic area led to a biphasic response, as shown by a decrease in intensity between 30 and 60 min of stimulation.3. The increase in fluorescence intensity caused by stimulation of the arcuate nucleus was completely prevented by pre-treatment with the tyrosine hydroxylase inhibitor alpha-methyl-tyrosine. Thus, the effect appears to be due to an enhancement of amine synthesis.4. The intensity values found after synthesis inhibition were used for a preliminary estimation of the catecholamine turnover time in the nerve cell bodies of the arcuate nucleus.5. In conclusion, electrical stimulation appears to induce a characteristic type of concentration change in the nerve cell body, at least under certain experimental conditions. It is compared with similar responses to physiological changes such as the reaction to acute cold exposure.     

大鼠下丘脑弓状核神经元的衰老性变化

选用青、中年和老年雄性大鼠各１０只，用形态计量学和体视学方法定量分析弓状核神经元年龄性变化。结果发现在老年大鼠弓状核，部分暗型和亮型神经元内粗面内质网排列紊乱、缩短和双层膜间隔增宽，线粒体嵴断裂、肿胀和空泡化，溶酶体，微管和颗粒小泡数减少；与青、中年组比较神经元数分别丢失３７％和２７％，核仁平均体积缩小３０％左右；