摘除侧眼球对大鼠视交叉上核节律性的影响

成年Ｗｉｓｔａｒ雌鼠５７只，随机分为实验组３０只，行双眼摘除术。对照组２７只。术后４周将各组动物体重相近的每３只列为一个配伍组，分别在０９：００－１０：００、１７：００－１８：００、２３：００－２４：００三个时间处死。将含有视交叉上核的脑组织经固定、恒冷箱切片后，用免疫组化ＡＢＣ法染色显示视交叉上核内含ＶＩＰ或ＡＶＰ的神经元，微机图像分析上测量光镜下这两种神经元的相对切面面积及平均免疫反应强度。结     

摘除松果腺对大鼠视交叉上核节律性的影响

成年Ｗｉｓｔａｒ雄性大鼠２０只，实验组１０只，行松果腺摘除术；对照组１０只。术后３０ｄ将实验组、对照组动物各半数在０９：００～１０：００和１６：００～１７：００分别处死。用免疫组化ＡＢＣ法显示视交叉上核内含ＶＩＰ的神经元；微机图像分析仪上测量其光镜下的切面面积及平均免疫反应强度。结果：（１）对照组不同时间处死的动物ＶＩＰ样神经元切面面积０９：００～１０：００大于１６：００～１７：００，呈节律性变化。（２）摘除松果腺后各时间组间ＶＩＰ样神经元切面面积的差异无显著性，提示实验组动物视交叉上核的ＶＩＰ样神经元功能活动的日周节律已发生改变。（３）对照组和实验组动物的ＶＩＰ样神经元平均免疫反应强度在所测的两个时间中均未见明显差异。     

双侧眼球摘除对大鼠视交叉上核的影响──免疫组化及光电镜体视学研究

采用双侧眼球摘除大鼠模型，术后存活不同时间，用免疫组化法探讨视交叉上核内ＶＩＰ和ＡＶＰ免疫反应强度和面积的变化；对变化明显的２１ｄ组进一步用光镜和电镜体现学方法进行形态学研究。＜１＞免疫组化研究：ＶＩＤ免疫染色，２１ｄ组免疫反应强度和面积均比对照组降低（Ｐ＜０．０５），２ｄ和７ｄ组免疫反应强度和面积与对照组相比无显著差异。ＡＶＰ免疫染色，三个时间实验组免疫反应强度和面积均与对照组无明显差异。＜２＞体视学研究：实验组ＶＩＰ样神经元胞体体积、胞核体积、核仁平均直径均明显缩小，粗面内质网和高尔基复合体表面积密度明显下降。以上所见提示摘除眼球２ｌｄ时，视交叉上核内直接接受光信息的ＶＩＰ样神经元的免疫活性下降是因阻断光传入所造成的。光传入的阻断和视神经纤维的溃变使视交叉上核中ＶＩＰ样神经元的结构呈现功能性改变，推测这些变化将引起该神经元肽类物质含量的下降。     

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．     

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…

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     

双侧眼球摘除对大鼠视交叉上核的影响—免疫组化及光电镜体视…

采用双侧眼球摘除大鼠模型，术后存活不同时间，用免疫组化法探讨视交叉上核内ＶＩＰ和ＡＶＰ免疫反应强度和面积的变化；对变化时明显的２１ｄ组进一步同光镜和电镜体视学方法进行形态学研究。＜１＞免疫组化研究：ＶＩＰ免疫染色，２１ｄ组免疫反应强度和面积均比对照组降低（Ｐ＜０．０５），２ｄ和７ｄ组免疫反应强度和面积与对照组相比无显著差异。ＡＶＰ免疫染色，三个时间实验组免疫反应强度和面积均与对照组无显著差异。＜２     

大鼠视交叉上核内VIP、AVP及SOM样神经元的分布及相互联系—免疫组化多重标记法研究

大鼠视交叉上核内ＶＩＰ、ＡＶＰ及ＳＯＭ样神经元的分布及相互联系──免疫组化多重标记法研究王蕾，欧可群，操高原，陈文玉华西医科大学成都６１００４１视交叉上核（ＳＣＮ）具有生物钟功能已为众多实验所证实，但对其节律发生并保持与外界同步的机制却尚在探索之中。...     

28周人胎视皮质含钙结合蛋白神经元的区域分布

用免疫细胞化学方法研究了２８周人视皮质１７区和１８区含ＣＡＬＢＩＮＤＮ（ＣＢ）及含ＰＡＲＶＡＬＢＵＭＩＮ（ＰＶ）神经元的分布。结果发现：１７区含ＣＢ及含ＰＶ神经元的数量均较１８区者多得多，与１８区比较，它们还可见于皮质较汪的层次，使１７／１８区交界处明显可辨。结合我们对人类新皮质含ＣＢ及含ＰＶ神经元的发育研究结果。本实验结果提示，人类视皮质１７区神经元的发育和成熟早于１８区神经元。     

人胎儿胸腺精氨酸-加压素、血管活性肠肽和5-羟色胺免疫反应细胞

目的：通过观察神经肽及生物胺在胸腺中的分布，探讨胸腺神经内分泌的性质和神经肽及生物胺在胸腺中的生物学意义。方法：应用胎儿胸腺冰冻切片，采用ＰＡＰ免疫组织化学法，行ＡＶＰ、ＶＩＰ和５－ＨＴ免疫组织化学染色。结果：在胸腺的实质和小叶间隔中均可见到ＡＶＰ、ＶＩＰ和５－ＨＴ免疫反应细胞。ＡＶＰ免疫反应细胞主要分布于被膜下皮质内，ＶＩＰ和５－ＨＴ免疫反应细胞主要分布于被膜下皮质区和皮髓质交界区。５－ＨＴ免疫反应细胞的数量为最多。结论：胎儿胸腺中存在着弥散神经内分泌细胞。它们可以产生ＡＶＰ、ＶＩＰ和５－ＨＴ，通过内分泌和旁分泌等方式，调节胸腺的生理功能。     

视网膜节细胞的轴突与视交叉上核内含VP神经元间联系的研究

视网膜节细胞的轴突与视交叉上核内含ＶＰ神经元间联系的研究（华西医科大学组织学研究室，成都６１００４４欧可群，操高原，陈文玉，王蕾，张军，马玉琼）视交叉上核（ｓｕｐｒａｃｈｉａｓｍａｔｉｃｎｕｃｌｅｕｓ，ＳＣＮ）是哺乳动物昼夜节律起搏器，为证实视交叉上...     

Contrary effect of eye enucleation on VIP-immunoreactive neurons in the suprachiasmatic nucleus and the superior colliculus of the rat

The topographic alternation of vasoactive intestinal peptide (VIP) immunoreactivity after long-term bilateral eye enucleation (80 days) was investigated in the suprachiasmatic nucleus (SCN) and the superior colliculus of the adult rat with the peroxidase-antiperoxidase method. In the SCN, the immunostaining of VIP-immunoreactive (IR) cell bodies increased, and the intensity and density of VIP-IR fibers and terminals were markedly enhanced after eye enucleation. On the other hand, after eye enucleation, no VIP-IR cell bodies and fibers were visible in the stratum griseum superficiale of the superior colliculus, although fusiform-shaped VIP-IR neurons were distributed in the layer of unoperated control rats. The present results, therefore, have revealed that the long-term blockage of retinal input induces changes of VIP immunoreactivity in different manners, according to the target brain areas.     

松果腺褪黑激素对大鼠下丘脑视交叉上核AVP、VIP日周分泌节律的影响

本文通过建立松果腺切除模型和松果腺褪黑激素注射模型，应用免疫组织化学和显微图象分析技术，分析了褪黑激素对下丘脑视交叉上核糖氨酸血管加压素、血管活性肠肽神经元昼夜分泌节律的不同影响。结果表明，褪黑激素影响血管活性肠肽神经元的昼夜分泌节律，而对血管加压素神经元无此影响，推测血管加压素神经元可能是视交叉上核昼夜节律起搏器作用的内在结构基础．     

Influences of feeding and drinking on circadian rhythms of opioid peptides in plasma, hypothalamus and pituitary gland in rats

Changes of plasma, hypothalamic and pituitary immunoreactive beta-endorphin (IR-beta-end), methionine-enkephalin (IR-Met-enk) and ACTH (IR-ACTH) were studied under various conditions of feeding and watering in rats. When rats were fed from 17:00 to 09:00 hr and water was given ad lib, plasma IR-beta-end and IR-ACTH had parallel circadian rhythms with a peak before feeding and drinking. In the hypothalamus, IR-beta-end and IR-Met-enk showed parallel circadian rhythms with a decrease before these behaviors. When rats were fed from 09:00 to 17:00 hr, the peaks of plasma IR-beta-end and IR-ACTH shifted to one hour before the onset of feeding and drinking. When feeding and watering were restricted to 17:00-09:00 hr and 09:00-12:00 hr respectively, plasma IR-beta-end and IR-ACTH exhibited parallel circadian rhythms with two separate peaks at one hour before drinking and feeding, respectively. In the hypothalamus, IR-beta-end, IR-Met-enk and IR-ACTH showed parallel circadian rhythms with a decrease before feeding but not before drinking. When rats were fed from 17:00 to 20:00 hr, plasma IR-beta-end increased and neurohypophysial IR-beta-end and IR-Met-enk decreased at 16:00 hr, one hour before feeding. It was observed that locomotor activities increased at the time of transition from light to dark and at one hour before the onset of feeding and drinking. The present results suggest that endogenous opioid peptides may have some physiological roles in feeding and drinking behaviors.     

Circadian rhythms of somatostatin-immunoreactivity in the suprachiasmatic nucleus of the rat.

Twenty-four hour patterns in somatostatin (SS)-like immunoreactivity (LI) within the suprachiasmatic nucleus (SCN) were determined by enzyme immunoassay in rats blinded by bilateral orbital enucleation or kept sighted under light-dark conditions. A remarkable circadian rhythm was found in the concentration of SS-LI in the SCN under blinded conditions. The peak time appeared at about circadian time (CT) 4 in the early subjective day and the trough at around CT 16 or 20 in the subjective night. Light-dark cycles did not alter the circadian patterns of SS-LI observed in the blinded rat SCN. These results indicate the presence of an endogenous circadian rhythm in SS-LI in the rat SCN, independent of environmental lightning cycles.     

Light exposure induces short- and long-term changes in the excitability of retinorecipient neurons in suprachiasmatic nucleus

The suprachiasmatic nucleus (SCN) is the locus of a hypothalamic circadian clock that synchronizes physiological and behavioral responses to the daily light-dark cycle. The nucleus is composed of functionally and peptidergically diverse populations of cells for which distinct electrochemical properties are largely unstudied. SCN neurons containing gastrin-releasing peptide (GRP) receive direct retinal input via the retinohypothalamic tract. We targeted GRP neurons with a green fluorescent protein (GFP) marker for whole cell patch-clamping. In these neurons, we studied short (0.5-1.5 h)- and long-term (2-6 h) effects of a 1-h light pulse (LP) given 2 h after lights off [Zeitgeber time (ZT) 14:00-15:00] on membrane potential and spike firing. In brain slices taken from light-exposed animals, cells were depolarized, and spike firing rate increased between ZT 15:30 and 16:30. During a subsequent 4-h period beginning around ZT 17:00, GRP neurons from light-exposed animals were hyperpolarized by ～15 mV. None of these effects was observed in GRP neurons from animals not exposed to light or in immediately adjacent non-GRP neurons whether or not exposed to light. Depolarization of GRP neurons was associated with a reduction in GABA(A)-dependent synaptic noise, whereas hyperpolarization was accompanied both by a loss of GABA(A) drive and suppression of a TTX-resistant leakage current carried primarily by Na. This suggests that, in the SCN, exposure to light may induce a short-term increase in GRP neuron excitability mediated by retinal neurotransmitters and neuropeptides, followed by long-term membrane hyperpolarization resulting from suppression of a leakage current, possibly resulting from genomic signals.     

Circadian feeding rhythm after hypothalamic knife-cut isolating suprachiasmatic nucleus

Bilateral parasagittal knife-cut between the suprachiasmatic nucleus (SCN) and lateral hypothalamic area (LH) or coronal knife-cut between the SCN and ventromedial hypothalamic nucleus (VMH) resulted in a partial loss of the circadian feeding rhythm in rats; after either operation the rats consumed about 30% of their total daily food intake during the light period. However, after the parasagittal and coronal knife-cuts were made in combination, the circadian feeding rhythm was completely lost (50% food intake during the light period). Rats which lost the circadian feeding rhythm partially or completely showed neither obesity nor anorexia. These findings suggest that there are dual informational pathways from the SCN, possibly between the SCN and LH and between the SCN and VMH, through which circadian time signals generated in the SCN are transmitted to the LH and VMH to drive the circadian feeding rhythm.     

Circadian periods of single suprachiasmatic neurons in rats

Neuronal activity of a single neuron was monitored continuously for more than 5 days by means of a multi-electrode dish in dispersed cell culture of the rat suprachiasmatic nucleus (SCN). Sixty-seven out of 88 neurons showed a robust circadian rhythm in firing rate. The mean circadian period was 24.2 h, which was almost identical to that of the locomotor activity rhythm in 114 weanling rats blinded on the day of birth. However, the circadian period in individual SCN neurons was scattered from 20.0 to 28.3 h (SD, 1.4 h), while the period of activity rhythm clustered from 24.0 to 24.8 h (SD, 0.2 h). It is concluded that a large number of SCN neurons contain the circadian oscillator, the period of which is more variable than the circadian period of the SCN as a whole. It is suggested that the circadian rhythms in individual SCN neurons are capable of synchronizing to each other and are integrated to constitute a multiple oscillator system(s) within the SCN.     

Circadian changes in arginine vasopressin level in the suprachiasmatic nuclei in the rat

Arginine vasopressin (AVP) neurons were preferentially localized in the dorsomedial part of the suprachiasmatic nucleus (SCN). To know the role of AVP neurons in the SCN, male rats were kept under a normal light-dark cycle (L-D), or under constant darkness (D-D) for 20 days. In L-D condition, AVP levels in the SCN showed the circadian change. In D-D condition, the patterns in AVP levels showed a free-running rhythm, and an about 12-h shift per 20 days. This result suggests that the activity of AVP neurons may be closely associated with the endogenous circadian rhythm of the SCN.