大鼠孤束核和延髓腹外侧区至下丘脑外侧区的儿茶酚胺能投射…

将ＨＲＰ注入下丘脑外侧区进行逆行追踪，并将之与抗ＦＯＳ和抗酪氨酸羧化酶双重免疫组织化学方法相结合，对大鼠孤束核和延髓腹外侧区至下丘脑外侧区的儿茶酚胺能投射神经元在胃伤害性刺激后的ｃ－ｆｏｓ表达进行了观察。光镜下见到孤束核和延髓腹外侧区出现七种不同的反应阳性细胞，即：ＨＲＰ、ＦＯＳ、ＴＨ单一反应阳性细胞，ＦＯＳ／ＨＲＰ、ＦＯＳ／ＴＨ、ＨＲＰ／ＴＨ双重反应阳性细胞和ＦＯＳ／ＨＲＰ／ＴＨ三重反应阳性细胞     

大鼠孤束核和延髓腹外侧区至下丘脑外侧区的儿茶酚胺能投射神经元在胃伤害性刺激后的FOS表达

将ＨＲＰ注入下丘脑外侧区进行逆行追踪，并将之与抗ＦＯＳ和抗酪氨酸羟化酶双重免疫组织化学方法相结合，对大鼠孤束核和延髓腹外侧区至下丘脑外侧区的儿茶酚胺能投射神经元在胃伤害性刺激后的ｃ－ｆｏｓ表达进行了观察．光镜下见到孤束核和延髓腹外侧区出现七种不同的反应阳性细胞，即：ＨＲＰ、ＦＯＳ、ＴＨ单一反应阳性细胞，ＦＯＳ／ＨＲＰ、ＦＯＳ／ＴＨ、ＨＲＰ／ＴＨ双重反应阳性细胞和ＦＯＳ／ＨＲＰ／ＴＨ三重反应阳性细胞．七种反应阳性细胞中以ＦＯＳ、ＴＨ单一反应阳性细胞和ＦＯＳ／ＴＨ双重反应阳性细胞数量较多，其余的各类均较少．ＨＲＰ阳性细胞主要见于注射侧，对侧偶见。上述七种阳性细胞主要分布在延髓中、尾段的孤束核内侧亚核和延髓腹外侧区，两者之间的网状结构中少见．本文结果证明大鼠孤束核和延髓腹外侧区儿茶酚胺能神经元有少量向下丘脑外侧区投射，其中少部分儿茶酚胺能神经元参与了胃伤害性刺激的传导或调控．     

睡眠-觉醒相关神经递质的研究进展

<正>失眠为常见的临床主诉之一。根据睡眠障碍国际标准(第3版),失眠的诊断标准为:患者尽管有充分的机会和环境睡眠,但仍然存在入睡困难或睡眠维持障碍,且影响第2天的日间功能^[1]。这种症状如每周发生3次以上并持续3月,则可诊断为失眠症。     

妊娠、分娩以及泌乳期大鼠下丘脑中食欲素及其受体表达的变化

目的 观察大鼠下丘脑中食欲素(Orexin)及其受体(OX1R、OX2R)在妊娠、分娩以及泌乳期表达的变化,以探讨Orexin与生殖功能之间的关系.方法 通过竞争性逆转录多聚酶链式反应(Competitive RT-PCR)和免疫组织化学方法测定大鼠下丘脑中Orexin前体(Prepro-OX)、Orexin-A、OX1R和OX2R在妊娠、分娩以及泌乳期的表达.结果 Orexin-A和OX1R阳性神经元主要分别存在于大鼠下丘脑外侧区(LHA)以及妊娠和泌乳期大鼠的下丘脑室旁核 (PVN)和视上核(SON).泌乳第1d的Prepro-Orexin mRNA和OX1R的表达水平明显高于妊娠后期和泌乳期.OX2R的表达在生殖各时期之间没有明显改变.结论 Orexin可能参与大鼠泌乳早期的生殖功能调节,下丘脑的PVN及SON可能是其重要的作用部位.     

中缝背核在睡眠-觉醒中的作用

中缝背核(DRN)是调控睡眠-觉醒的重要核团,在脑内有着广泛的神经投射区域。DRN位于中脑导水管腹侧,主要由5-羟色胺(5-HT)、γ-氨基丁酸(GABA)、多巴胺(DA)和谷氨酸(Glu)能4类神经元构成。本文主要介绍了DRN的各类神经元在睡眠-觉醒中相关作用的最新研究进展。     

小鼠未定带至PAG腹外侧区特异性神经元通路的形态学研究

目的:利用囊泡膜谷氨酸转运体2(VGluT2)-ires-cre、谷氨酸脱羧酶2(GAD2)-ires-cre和羟色胺转运体(Sert)-ires-cre小鼠结合重组狂犬病毒介导的逆行跨单级突触追踪技术,研究未定带(ZI)和中脑导水管周围灰质腹外侧区(vlPAG)内特异性神经元之间的纤维联系。方法:首先将辅助病毒注入转基因小鼠右侧vlPAG内,两周过后将重组狂犬病毒(RV)注入相同区域。一周后,在激光共聚焦显微镜下观察RV标记的突触前神经元在ZI内的分布。结果:将RV注入vlPAG后,在VGluT2-ires-cre小鼠ZI的吻尾方向上均可观察到逆标的突触前神经元分布;GAD2-ires-cre小鼠逆标神经元只见于ZI吻侧部,但Sert-ires-cre小鼠ZI内少见RV逆行标记的突触前神经元。结论:ZI神经元发出投射至vlPAG,作用于其中的谷氨酸能神经元或GABA能神经元,该通路可能参与了疼痛或恐惧样行为的调控。     

原发性高血压状态下血管紧张素Ⅱ1型受体在下丘脑及延髓头端腹外侧区的表达

目的观察WKY大鼠和自发性高血压大鼠(SHR)下丘脑室旁核(PVN)、视上核(SON)和延髓头端腹外侧区(RVLM)内血管紧张素Ⅱ1型受体(AT-1R)的表达。方法应用免疫荧光染色技术。结果两组大鼠PVN、SON、RVLM内AT-1R免疫阳性神经元的分布与形态基本类似。SHR大鼠PVN、SON和RVLM内AT-1R阳性细胞数目较WKY组多,荧光强度也较对照组强。结论本研究提示AT-1R在下丘脑和RVLM内的血压神经内分泌调节活动中起着重要的介导作用,原发性高血压的发生发展与脑内AT-1R的异常增加所致的对AngⅡ反应性增强有关。     

Astrocytic gap junctions in the rat lateral hypothalamic area

An extensive system of gap or nexus junctions has been found between astrocytic processes in the neuropil of the lateral hypothalamic area in the albino rat. These specialized interastrocytic junctions occur in regions of high synaptic density where neural processes are separated by the interconnected glial system. In this study, 90% of the gap junctions observed in the lateral hypothalamic neuropil are in the immediate proximity of synaptic terminals. The close morphological relationship of these glial gap junctions with synaptic contacts suggests that they may play a significant role in the process of synaptic transmission.     

Dependence of the anterior olfactory area self-stimulation upon the lateral hypothalamic area

The functional relation between the anterior olfactory area (AO) and the lateral hypothalamic area (LH) was examined in a self-stimulation situation. Bar-pressing responses for AO sitmulation were suppressed by unilateral injection of procaine, and enhanced by glutamate, into LH. Neither procaine nor glutamate injected into AO had any influence upon LH self-stimulation. It is unlikely that the procaine effect was due to motor disturbance because similar injection of procaine into LH did not disturb the performance of a one-way avoidance task. It appears that the rewarding effect of AO stimulation is dependent upon the excitation of the more caudal structures including LH.     

Distribution of retinal axons within the lateral hypothalamic area

Summary Intraocular injections of tritiated leucine were performed in normal and in unilaterally enucleated adult albino rats. Light microscopical evaluation of the autoradiograms revealed evidence for retinal afferents to distribute within a rather circumscribed area of the lateral hypothalamus. The silver grains were consistently, however, observed only in the group of enucleated animals, indicating differential transport under basic and experimental conditions.     

Astrocytic gap junctions in the rat lateral hypothalamic area.

An extensive system of gap or nexus junctions has been found between astrocytic processes in the neuropil of the lateral hypothalamic area in the albino rat. These specialized interastrocytic junctions occur in regions of high synaptic density where neural processes are separated by the interconnected glial system. In this study, 90% of the gap junctions observed in the lateral hypothalamic neuropil are in the immediate proximity of synaptic terminals. The close morphological relationship of these glial gap junctions with synaptic contacts suggests that they may play a significant role in the process of synaptic transmission.     

The substrate for brain-stimulation reward in the lateral preoptic area: III. Connections to the lateral hypothalamic area

Double-pulse tests were used to estimate the refractory periods and anatomical linkage of the reward-relevant fibers that course between the lateral preoptic and lateral hypothalamic areas. In the 1st study, pairs of conditioning and test pulses were delivered to each site, and the interval between pulses varied; recovery from refractoriness was similar at both sites, with the curves generally rising from 0.6 to 2.0 ms. In the 2nd study, the pairs of pulses were delivered to both sites. Six of 7 rats showed evidence of axonal collision, with estimates of conduction velocity that ranged from 0.48 to 8.95 m/s across rats. These results suggest that a wide spectrum of fiber types characterizes the reward-relevant axons that course uninterruptedly between these 2 regions.     

Sleep-waking discharge patterns of neurons recorded in the rat perifornical lateral hypothalamic area

The perifornical lateral hypothalamic area (PF-LHA) has been implicated in the control of several waking behaviours, including feeding, motor activity and arousal. Several cell types are located in the PF-LHA, including projection neurons that contain the hypocretin peptides (also known as orexins). Recent findings suggest that hypocretin neurons are involved in sleep-wake regulation. Loss of hypocretin neurons in the human disorder narcolepsy is associated with excessive somnolence, cataplexy and increased propensity for rapid eye movement (REM) sleep. However, the relationship of PF-LHA neuronal activity to different arousal states is unknown. We recorded neuronal activity in the PF-LHA of rats during natural sleep and waking. Neuronal discharge rates were calculated during active waking (waking accompanied by movement), quiet waking, non-REM sleep and REM sleep. Fifty-six of 106 neurons (53 %) were classified as wake/REM-related. These neurons exhibited peak discharge rates during waking and REM sleep and reduced discharge rates during non-REM sleep. Wake-related neurons (38 %) exhibited reduced discharge rates during both non-REM and REM sleep when compared to that during waking. Wake-related neurons exhibited significantly higher discharge rates during active waking than during quiet waking. The discharge of wake-related neurons was positively correlated with muscle activity across all sleep-waking states. Recording sites were located within the hypocretin-immunoreactive neuronal field of the PF-LHA. Although the neurotransmitter phenotype of recorded cells was not determined, the prevalence of neurons with wake-related discharge patterns is consistent with the hypothesis that the PF-LHA participates in the regulation of arousal, muscle activity and sleep-waking states.     

Ovarian influences on body weight regulation in rats with lateral hypothalamic lesions

The effect of lateral hypothalamic lesions upon the level of maintained body weight was studied in gonadally intact and ovariectomized female rats. The body weight of both the gonadally intact and ovariectomized animals declined after lesioning; but, while the weight level of the ovariectomized animals remained approximately 10% below normal, the body weight of the intact group steadily approached that of nonlesioned controls. This result suggests that ovarian factors contribute to the smaller effect on body weight as reported by others for females with lateral hypothalamic lesions. Further support for this hypothesis was found in the observations that (1) the reduced effect of lateral hypothalamic lesions on body weight of gonadally intact females was associated with prolonged periods of diestrus and (2) the normal weight suppressing effects of estrogen were attenuated by lateral hypothalamic lesions in the ovariectomized animals.