• The Korean Journal of Physiology and Pharmacology
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• 제28권6호
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• pp.569-576
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• 2024

Norepinephrine (NE) modulates synaptic transmission and long-term plasticity through distinct subtype adrenergic receptor (AR)-mediated-intracellular signaling cascades. However, the role of NE modulates glutamatergic long-term potentiation (LTP) in the hypothalamic paraventricular nucleus (PVN) magnocellular neuroendocrine cells (MNCs) is unclear. We here investigate the effect of NE on high frequency stimulation (HFS)-induced glutamatergic LTP in rat hypothalamic PVN MNCs in vitro, by whole-cell patch-clamp recording, biocytin staining and pharmacological methods. Delivery of HFS induced glutamatergic LTP with a decrease in N2/N1 ratio in the PVN MNCs, which was enhanced by application of NE (100 nM). HFS-induced LTP was abolished by the blockade of N-methyl-D-aspartate receptors (NMDAR) with D-APV, but it was rescued by the application of NE. NE failed to rescue HFS-induced LTP of MNCs in the presence of a selective β1-AR antagonist, CGP 20712. However, application of β1-AR agonist, dobutamine HCl rescued HFS-induced LTP of MNCs in the absence of NMDAR activity. In the absence of NMDAR activity, NE failed to rescue HFS-induced MNC LTP when protein kinase A (PKA) was inhibited by extracellular applying KT5720 or intracellular administration of PKI. These results indicate that NE activates β1-AR and triggers HFS to induce a novel glutamatergic LTP of hypothalamic PVN NMCs via the postsynaptic PKA signaling pathway in vitro in rats.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1999년도 학술발표회 진행표 및 논문초록
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• pp.58-58
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• 1999

The paraventricular nucleus (PVN) is a complex structure comprised of several different populations of cells divided into two main groups, the magnocellular (type I) neurons which secrete vasopressin and oxytocin and the parvocellular (type II) neurons which regulate hormone secretion from the anterior pituitary.(omitted)

• 동의생리병리학회지
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• 제23권4호
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• pp.805-817
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• 2009

This study was to investigate central localization of neurons projecting to the urinary bladder and urinary bladder-related acupoints(Wijung, $BL_{40}$) and neurons of immunoreactive to hormones and hormone receptors regulating urinary bladder function by using peudorabies virus(PRV). In this experiment, Bartha's strain of pseudorabies virus was used in rats to trace central localization of urinary bladder-related neurons and urinary bladder-related acupoints($BL_{40}$) which can regulate urinary system. PRV was injected into the urinary bladder and acupoints($BL_{40}$) related urinary system. After six days survival of rats, mainly common labeled neurons projecting to the urinary bladder and urinary bladder-related acupoints were identified in spinal cord, medulla, pons and diencephalon by PRV immunohistochemical staining method. First-order PRV labeled neurons projecting to urinary bladder and urinary bladder-related acupoints were found in the cervical, thoracic, lumbar and sacral spinal cord. Commonly labeled preganglionic neurons were labeled in the lumbosacral spinal cord and thoracic spinal cord. They were found in the lateral horn area(sacral parasympathetic nucleus and intermediolateral nucleus), lamina V-X, intermediomedial nucleus and dorsal column area. The area of sensory neurons projecting to urinary bladder and Wijung($BL_{40}$) was L5-S2 spinal ganglia and T12-L1 spinal ganglia, respectively. In the brainstem, the neurons were labeled most evidently and consistently in the nucleus of tractus solitarius, area postrema, dorsal motor nucleus of vagus nerve, reticular nucleus, raphe nuclei(obscurus, magnus and pallidus), C3 adrenalin cells, parapyramidal area(lateral paragigantocellular nucleus), locus coeruleus, subcoeruleus nucleus, A5 cell group, Barrington's nucleus and periaqueductal gray matter. In the diencephalon, PRV labeled neurons were marked mostly in the paraventricular nucleus and a few ones were in the lateral hypothalamic nucleus, posterior hypothalamic nucleus, ventromedial hypothalamic nucleus, arcuate nucleus, median eminence, perifornical nucleus, periventricular nucleus and suprachiasmatic nucleus. In cerebral cortex, PRV labeled neurons were marked mostly in the frontal cortex, 1,2 area, hind limb area, agranular insular cortex. Immunoreactive neurons to Corticotropin releasiing factor(CRF), Corticotropin releasiing factor-receptor(CRF-R), c-fos and serotonin were a part of labeled areas among the virus-labeled neurons of urinary bladder and Wijung($BL_{40}$). The commonly labeled areas were nucleus tractus solitarius, area postrema, reticular nucleus, raphe nuclei(obscurus, magnus and pallidus), locus coeruleus, A5 cell group, Barrington,s nucleus, arcuate nucleus, paraventricular nucleus, frontal cortex 1, 2 area, hind limb, and perirhinal(agranular insular) cortex. These results suggest that overlapped CNS locations are related with autonomic nuclei which regulate the functions of urinary bladder-relate organs and it was revealed by tracing PRV labeled neurons projecting urinary bladder and urinary bladder-related acupoints. These commonly labeled areas often overlap with the neurons connected with hormones and hormone receptors related to urination.

• Journal of Nutrition and Health
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• 제34권7호
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• pp.727-733
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• 2001

The present study was conducted to identify the mechanism about the regulation of appetite by examining the expression patterns of neuropeptide Y in the hypothalamus of mice either fasting mouse for 24 hours or with anorexia mutant mouse. In order to investigate the patterns of expression of neurpeptide Y, immunohistochemistry was employed for measurements at the tissue level, along with the molecular biological techniques of reverse transcription polymerase chain reaction(RT-PCR) and dot blotting. The results of this study are as follows. The level of expression of neruopeptide Y, a neuropeptide known to enhance appetite, was shown to be lowered in the arcuate nucleus(ARC), paraventricular nucleus(PVN), lateral hypothalamic area(LHA), and dorsomedial hypothalamic nucleus(DMN) in both the fasting and anorexia mutant groups when measured via immunohistochemistry, a tissue-level method. RT-PCR and dot blotting, the molecular biological methods employed in this study, revealed that the level of neuropeptide Y mRNA in the entire hypothalamus was similar in the control and fasting groups and lower in the anorexia mutant group. The results of the present study showed that while the levels of expression of the neuropeptide Y in the various hypothalamic regions studied did not exhibit regular increases or decreases when measured immunohistochemically. But the entire hypothalamus via molecular biological methods showed that the changes in these levels were more definite in the anorexia mutant group than in the fasting group.

• Molecules and Cells
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• 제23권1호
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• pp.88-93
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• 2007

Neuropeptide Y (NPY) is an orexigenic and hypothermic peptide. To understand its role in hypothermic conditions, male rats were placed in a $24^{\circ}C$ or $4^{\circ}C$ air chamber for 1.5 h. The expression of c-Fos protein, and NPY mRNA and protein, was analyzed in the hypothalamus 1 h-2 h later. The cold treatment increased the number of c-Fos-immunoreactive cells in the paraventricular hypothalamic nucleus (PVN) and arcuate nucleus (ARC). At the same time it decreased the density of NPY-immunoreactive components in the PVN, dorsomedial hypothalamic nucleus and ARC, as well as of NPY transcripts in the PVN and ARC. No colocalization of c-Fos with NPY was detected. These results suggest that short-term cold exposure should reduce indirectly NPY production in some hypothalamic nuclei to facilitate thermogenesis without inducing feeding behavior.

• The Korean Journal of Physiology and Pharmacology
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• 제5권1호
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• pp.41-46
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• 2001

To investigate the mutual relationship between angiotensin II (Ang II) and nitric oxide (NO) in paraventricular nucleus (PVN), Ang II receptor type Ia $(AT_{1A}),$ type Ib $(AT_{1B}),$ endothelial constitutive nitric oxide synthase (ecNOS), and neuronal constitutive nitric oxide synthase (ncNOS) mRNA levels of rat PVN were measured after unilateral carotid artery ligation. $AT_{1A}$ and $AT_{1B}$ mRNA levels were markedly elevated 6 hrs after unilateral carotid artery ligation. Losartan injection $(10\;{\mu}g/0.3\;{\mu}l)$ into the PVN augmented of the increment of $AT_{1A}$ and $AT_{1B}$ mRNAs It also increased ecNOS gene expression. In addition, $AT_{1B}$ mRNA levels increased after N-nitro-L-arginine methyl ester (L-NAME) injection $(50\;{\mu}g/0.3\;{\mu}l)$ into the PVN. These results suggest that Ang II and NO in the rat PVN may interplay, at least in part, through regulation of gene expression of ecNOS and $AT_{1B},$ respectively.

• 대한수의학회지
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• 제35권4호
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• pp.671-681
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• 1995

This study was attempted to investigate the topographical distribution, shape and immunoreactivity of growth hormone-releasing factor(GRF)- and somatostatin(SOM)-immunoreactive neurons in the hypothalamus of the Korean squirrels(Sciurus vulgalis coreae). For the light microscopical examination of immunohistochemistry, the brains were fixed with 4% paraformaldehyde solution by means of intracardiac perfusion. And the frozen sections($40{\mu}m$ thick) were stained immunohistochemically by ABC method. Distribution of GRF immunoreactive neurons($12-17{\mu}m$) was highest in the paraventricular nucleus, moderate in the periventricular and supraoptic nuclei, and low in the arcuate nucleus and lateral hypothalamic area. Their immunoreactive fibers were found very high in the median eminence, moderately in the supraoptic, paraventricular and periventricular nuclei, and low in the arcuate nucleus and lateral hypothalamic area. SOM immunoreactive perikarya($14-18{\mu}m$) were found moderately in the periventricular nucleus near the subependymal layer of the third ventricle, and low in the arcuate and suprachiasmatic nuclei. SOM immunoreactive fibers were found high in the median eminence, and moderately or low in the arcuate and periventricular nuclei.

• The Korean Journal of Physiology and Pharmacology
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• 제15권3호
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• pp.163-169
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• 2011

Corticosterone is known to modulate GABAergic synaptic transmission in the hypothalamic paraventricular nucleus. However, the underlying receptor mechanisms are largely unknown. In the anterior hypothalamic area (AHA), the sympathoinhibitory center that project GABAergic neurons onto the PVN, we examined the expression of glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) of GABAergic neurons using intact GAD65-eGFP transgenic mice, and the effects of corticosterone on the burst firing using adrenalectomized transgenic mice. GR or MR immunoreactivity was detected from the subpopulations of GABAergic neurons in the AHA. The AHA GABAergic neurons expressed mRNA of GR (42%), MR (38%) or both (8%). In addition, in brain slices incubated with corticosterone together with RU486 (MR-dominant group), the proportion of neurons showing a burst firing pattern was significantly higher than those in the slices incubated with vehicle, corticosterone, or corticosterone with spironolactone (GR-dominant group; 64 vs. 11~14%, p<0.01 by $x^2$-test). Taken together, the results show that the corticosteroid receptors are expressed on the GABAergic neurons in the AHA, and can mediate the corticosteroid-induced plasticity in the firing pattern of these neurons. This study newly provides the experimental evidence for the direct glucocorticoid modulation of GABAergic neurons in the AHA in the vicinity of the PVN.

• Journal of Acupuncture Research
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• 제17권2호
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• pp.261-276
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• 2000

본 실험은 pseudorabies 바이러스 (PRV) 의 Bartha strain 을 안면신경의 측두지, 하지를 지배하는 신경 (좌골신경) 및 상지를 지배하는 신경 (요골, 척골, 정중신경) 에 주입한 후 4 일간의 생존시간이 경과한 후 척수와 뇌를 적출하여 동결절편을 제작한 후 면역조직화학적 염색기법과 X-gal 조직화학 염색법을 시행하여 염색된 신경세포체를 척수와 뇌에 투사된 공통영역을 관찰하고 두침의 영역중 하나인 운동구와 사지와의 관계에 대한 실험적 증거를 제시하고자 시행하였다. 위의 실험에서 얻어진 결과는 아래와 같다. 1. 안면신경의 측두지, 하지를 지배하는 신경 (좌골신경) 및 상지를 지배하는 신경 (요골, 측골, 정중신경) 에서 투사된 공통된 영역은 척수에서 경수의 층판 1-IV, 흉수의 intermediolateral nucleus(IML), dorsal nucleus(D) 및 층판 X, 요수의 층판 IV, V, 천수의 층판 IV, V, IX, X 등의 영역에서 관찰되었고, 뇌줄기에서는 caudoventrolateral reticular nucleus(CVL), nucleus solitary tract(Sol), rostroventrolateral nucleus(RVL), area postrema(AP), raphe nuclei(raphe pallidus, raphe obscurus, raphe magnus), inferior olivary nucleus 의 등쪽부분 (gigantocellular reticular nucleus, Gi), Kolliker-Fuse nucleus(KF), central gray(CG), dorsal raphe nucleus (DR) and A5 영역에 표지된다. 또한 paraventricular hypothalamic nucleus(PRV) 와 lateral hypothalamic reticular nucleus(LH)에서도 관찰되고 locus coeruleus(LC) 와 subcoeruleus nuc!eus(SubCA) 에서도 관찰된다.

• Animal cells and systems
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• 제9권3호
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• pp.145-152
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• 2005

A retrograde tracer, WGA-apo-HRP-gold, was injected into midline thalamic nuclei and subsequently orexin-A immunostaining was performed on the tuberal region of the hypothalamus in order to investigate orexinergic projections to the midline thalamus. Injection site was targeted within one specific region, i.e., paraventricular, centromedian, rhomboid, reuniens, or intermediodorsal nucleus, but it proved to be either one or a combination of these thalamic nuclei. The distribution of WG/orexin-double-labeled neurons exhibited a general pattern in that the majority of labeled cells were observed within the ventral portion of the lateral hypothalamus as well as the perifornical nucleus (PeF). A small number of double-labeled cells were also observed at the dorsomedial nucleus, the area dorsal to the PeF, dorsal portion of the lateral hypothalamus, and the posterior hypothalamus. These orexin-immunoreactive neurons might have wake-related influences over a variety of functions related with midline thalamic nuclei, which include autonomic control, associative cortical functions, and limbic regulation.