• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.3
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• pp.195-204
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• 2011

Introduction: This study examined the regulatory mechanism underlying the meal-induced changes in the hypothalamic-pituitary-adrenal gland (HPA) axis activity. Materials and Methods: Male Sprague-Dawley rats (250-300 g) were hired for two different experiments as follows; 1) rats received either 8% sucrose or 0.2% saccharin ad libitum after 48 h of food deprivation with the gastric fistula closed (real feeding) or opened (sham feeding). 2). rats received 5 ml of intra-oral infusion with 0.2% saccharin or distilled water after 48 h of food deprivation. One hour after food access, all rats were sacrificed by a transcardiac perfusion with 4% paraformaldehyde. The brains were processed for c-Fos immunohistochemistry and the cardiac blood was collected for the plasma corticosterone assay. Results: Real feedings with sucrose or saccharin and sham feeding saccharin but not sucrose, following food deprivation decreased the plasma corticosterone level. c-Fos expression in the nucleus tractus of solitarius (NTS) of the fasted rats was increased by the consumption of sucrose but not saccharin, regardless of the feeding method. On the other hand, the consumption of sucrose or saccharin with real feeding but not the sham, induced c-Fos expression in the paraventricular nucleus (PVN) of the fasted rats. The intra-oral infusion with saccharin or water decreased the plasma corticosterone level of the fasted rats. Intra-oral water infusion increased c-Fos expression in both the PVN and NTS, but saccharin only in the NTS in the fasted rats. Conclusion: Neither restoration of the fasting-induced elevation of plasma corticosterone nor the activation of neurons in the PVN and NTS after refeeding requires the palatability of food or the post-ingestive satiety and caloric load. In addition, neuronal activation in the hypothalamic PVN may not be an implication in the restoration of the fasting-induced elevation of the plasma corticosterone by oropharyngeal stimuli of palatable food.

• The Journal of Korean Medicine
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• v.30 no.3
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• pp.28-38
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• 2009

Background : Peripheral nerve injuries are a commonly encountered clinical problem and often result in a chronic pain and severe functional deficits. Objective : The aim of this study was to evaluate the effects of Gentianae Macrophyllae Radix (G. M. Radix) on the pain control and the recovery of the locomotor function that results from the sciatic crushed nerve injury in rats. Method : Using rats, we crushed their sciatic nerve, and then orally administered the aqueous extract of G. M. Radix. The effects of G. M. Radix on the recovery locomotor function were investigated by walking track analysis. The effects of G. M. Radix on pain control were investigated by brain-derived neurotrophic factor (BDNF) expression in the sciatic nerve, and c-Fos expression in the paraventricular nucleus (PVN) of the hypothalamus and in the ventrolateral periaqueductal gray (vlPAG). Result : G. M. RADIX facilitates motor function from the locomotor deficit, and thereby increased BDNF expression and suppressed painful stimuli in the PVN and vlPAG after sciatic crushed nerve injury. Conclusion : It is suggested that G. M. Radix might aid recovery locomotor function and control pain after sciatic crushed nerve injury. Further studies on identifying specific the component in G.M. Radix associated with enhanced neural activity in the peripheral nerve injury may be helpful to develop therapeutic strategies for the treatment of peripheral nerve injury.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.6
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• pp.1053-1058
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• 2010

Glycyrrhizae radix (GR) is an herbal medicine commonly used in East Asia for treating a variety of diseases, including stomach disorders. In this study, the antidepressant-like activity of GR was investigated using the forced swimming test (FST) in rats. After the FST, the expression of c-Fos and corticotrophin releasing factor (CRF) was assessed by immunochemistry of brain samples from the paraventricular nucleus of the hypothalamus (PVN). The results of the FST showed that a high dose (400 mg/kg) of extract was very effective in reducing immobility(P<0.01), and increased climbing. In addition, treatment with GR (400 mg/kg) significantly decreased the expression of c-Fos and CRF in the PVN, compared to controls. In conclusion, the findings of this study demonstrated that GR effectively reduced behavioral and physiological depression responses in an animal model of depression, suggesting that GR might be useful in the treatment of clinical depression.

• Journal of Korean Physical Therapy Science
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• v.9 no.4
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• pp.53-61
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• 2002

This study was carried out to investigate the effects of electrical stimulation on the change oxytocin(OT) immunoreactive cells in the hypothalamus of the male SD rats. Fifteen healthy and normal male rats were divided into three groups, 5 SD rat in each group. The one group has been stimulated by electro-acupuncture(EA, 2Hz) for 30 min and the other group by EA for 1hr 30 min and control group has not been stimulated. The results were summarized as follows. OT immunoreactive cells were found in the Paraventricular nucleus (PVN), Supraoptic nucleus(SON) and Lateral Magnocellular Area(LMA). The number of OT immunoreactive cells of PVN were significantly increased after 30 min as compared with control group (p<0.05) and were also significantly increased after 1hr 30min than 30 min(p<0.05). The number of OT immunoreactive cells of SON were significantly increased after 30 min and 1hr 30 min(p<0.05) as compared with control group, but decreased after 1hr 30 min than 30 min. The number of immunoreactive hells of LMA significantly increased after 30 min(p<0.05) as compared with control group, but significantly decreased after 1hr 30 min than 30 min(p<0.05). These results show that OT is released into the hypothalamus in response to electrical stimulation.

• Science of Emotion and Sensibility
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• v.10 no.3
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• pp.411-418
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• 2007

Exposure to low frequency noise(LFN) can lead to vibroacoustic diseases(VADs), which include a systemic disease with lesions in a broad spectrum of organs and a psychiatric condition. It is known that VAD is an established risk factor for the development of many psychological conditions in humans and rodents, including major depression and anxiety disorder. The present study investigated the effects of LFN on neuronal stress responses in the rat brain. The neuronal expression of the proto-oncogene c-fos in the paraventricular nucleus(PVN) of the hypothalamus and tyrosine hydroxylase(TH) in the LC was observed. The immunocytochemical detection of the Fos protein and TH has been used as a marker of neuronal activation in response to stress. In addition, corticosterone concentration was evaluated by using an enzyme-linked immunosorbent assay(ELISA). The LFN groups were exposed to 32.5Hz and 125Hz of noise(4hr/day for 2days). The numbers of c-fos and TH-immunoreactive cells in the PVN and LC were significantly increased in the LFN groups(32.5Hz and 125Hz) compared to the normal group. Corticosterone concentration in plasma was also increased in LFN groups. The present results demonstrated that exposure with LFN produced a pronounced increase in expression of c-Fos and TH in stress-relevant brain areas. These results suggest that the neural characteristics involved in LFN are similar to those activated by typical processive stressors. These results also suggest that the central and peripheral activations by LFN may be related to LFN-related negative behavioral dysfunctions such as VADs.

• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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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)

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.2
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• pp.121-125
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• 2013

The purpose of this study is to investigate the antinociceptive effects of ginsenosides on toothache. c-Fos immunoreactive (IR) neurons were examined after noxious intrapulpal stimulation (NS) by intrapulpal injection of 2 M KCl into upper and lower incisor pulps exposed by bone cutter in Sprague Dawley rats. The number of Fos-IR neurons was increased in the trigeminal subnucleus caudalis (Vc) and the transitional region between Vc and subnucleus interpolaris (Vi) by NS to tooth. The intradental NS raised arterial blood pressure (BP) and heart rate (HR). The number of Fos-IR neurons was also enhanced in thalamic ventral posteromedial nucleus (VPMN) and centrolateral nucleus (CLN) by NS to tooth. The intradental NS increased the number of Fos-IR neurons in the nucleus tractus solitarius (NTS) and rostral ventrolateral medulla (RVLM), hypothalamic supraoptic nucleus (SON) and paraventricular nucleus (PVN), central cardiovascular regulation centers. Ginsenosides reduced the number of c-Fos-IR increased by NS to tooth in the trigeminal Vc and thalamic VPMN and CLN. Naloxone, an opioid antagonist, did not block the effect of ginsenoside on the number of Fos-IR neurons enhanced by NS to tooth in the trigeminal Vc and thalamic VPMN and CLN. Ginsenosides ameliorated arterial BP and HR raised by NS to tooth and reduced the number of Fos-IR neurons increased by NS to tooth in the NTS, RVLM, hypothalamic SON, and PVN. These results suggest that ginsenosides have an antinociceptive effect on toothache through non-opioid system and attenuates BP and HR increased by NS to tooth.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.2
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• pp.143-158
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• 2011

Objectives : Peripheral nerve injuries are commonly encountered clinical problem and often result in severe functional deficits. The aim of this study is to evaluate the effects of aqueous extract of Achyranthes japonica(AJ) on functional recovery in sciatic nerve after crushed sciatic nerve injury. Methods : In the present study, the animals in the AJ-treated groups received the aqueous extract of AJ at the respective doses orally for 13 consecutive days. In order to assess the effects of the aqueous extract of AJ on function recovery in crushed sciatic nerve injury, sciatic functional index(SFI) was performed. c-Fos expression in the paraventricular nucleus(PVN) and ventrolateral periaqueductal gray(vIPAG), and neurofilament, and the expressions of brain-derived neurotrophic factor(BDNF), nerve growth factor(NGF) following crushed sciatic nerve injury in rats were investigated. For this, immunohistochemistry and western blot were performed. Results : In the present study, crushed sciatic nerve injury showed characteristic gait changes showing decrease of SFI value and treatment with the aqueous extract of AJ significantly enhanced the SFI value. Neurofilament expression in the sciatic nerve was decreased by crushed sciatic nerve injury and treatment with the AJ increased neurofilament expression. The expressions of BDNF and NGF in the sciatic nerve were increased following crushed sciatic nerve injury and treatment with the AJ significantly controlled the sciatic nerve injury-induced increment of BDNF and NGF expressions. c-Fos expressions in the PVN and vIPAG were increased following crushed sciatic nerve injury and treatment with the AJ significantly suppressed the sciatic nerve injury-induced increment of c-Fos expressions. Conclusions : These results suggest that AJ treatment after crushed sciatic nerve injury is effective in the functional recovery by enhancing axonal regeneration and suppressing of pain.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.2
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• pp.125-142
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• 2011

Objectives : Peripheral nerve injuries are commonly encountered clinical problems and often result in severe functional deficits. The purpose of this study was to evaluate the effects of Haein-tang(Hairen-tang) extract on functional recovery and pain release in the sciatic nerve after crushed sciatic nerve injury in rats. Methods : 1. Sciatic functional index(SFI) were performed on functional recovery. 2. c-Fos immunohistochemistry were performed on c-Fos expressions in the paraventricular nucleus(PVN) and ventrolateral periaqueductal gray(vIPAG). 3. Neurofilament immunohistochemistry were performed on neurofilament regeneration. 4. Western blot were performed on brain-derived neurotrophic factor(BDNF) and nerve growth factor(NGF) expression. Results : 1. Haein-tang(Hairen-tang) extract significantly enhanced the SFI value in the sciatic nerve injury and 100 mg/kg, 200 mg/kg Haein-tang(Hairen-tang)-treated group. 2. Haein-tang(Hairen-tang) extract significantly suppressed the sciatic nerve injury-induced increment of c-Fos expressions in the PVN and vIPAG in the sciatic nerve injury and 100 mg/kg, 200 mg/kg Haein-tang(Hairen-tang)-treated group. 3. Haein-tang(Hairen-tang) extract significantly increased neurofilament expression in the sciatic nerve injury and 50 mg/kg, 100 mg/kg, 200 mg/kg Haein-tang(Hairen-tang)-treated group. 4. Haein-tang(Hairen-tang) extract significantly controled the sciatic nerve injury-induced increment of BDNF and NGF expressions in the sciatic nerve injury and 100 mg/kg, 200 mg/kg Haein-tang(Hairen-tang)-treated group. Conclusions : These results suggest that Haein-tang(Hairen-tang) treatment after sciatic nerve injury is effective for the functional recovery by enhancing of axonal regeneration and suppressing of pain.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.3
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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.