• Natural Product Sciences
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• v.19 no.4
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• pp.337-341
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• 2013

The effects of gypenosides (GPS) on electric footshock (EF)-induced acute stress in mice were investigated. Mice were treated orally with GPS (30-400 mg/kg) once a day for 5 days. After 2 days of GPS treatment, mice were exposed to EF stimuli (intensity, 2 mA; interval, 10 s; duration, 3 min) for acute stress for 3 days. Spontaneous locomotor activity was increased by acute EF stress, which was decreased by treatment with GPS (100 and 400 mg/kg). In addition, the increased levels of dopamine and serotonin by acute EF stress in the brain were reduced by treatment with GPS (100 and 400 mg/kg). The serum levels of corticosterone increased by acute EF stress were also reduced by GPS (100 and 400 mg/kg). These results suggest that GPS shows the ameliorating effects on acute EF stress by modulating the activity of dopaminergic and serotonergic neurons, and the serum levels of corticosterone. Clinical trials of GPS need to be conducted further so as to develop promising anti-stress agents.

• Journal of Yeungnam Medical Science
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• v.31 no.1
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• pp.1-8
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• 2014

Dizziness can be classified mainly into 4 types: vertigo, disequilibrium, presyncope, and lightheadedness. Among these types, vertigo is a sensation of movement or motion due to various causes. The main causes of peripheral vertigo are benign paroxysmal positional vertigo (BPPV), acute vestibular neuritis (AVN), and Meniere's disease. BPPV is one of the most common causes of peripheral vertigo. It is characterized by brief episodes of mild to intense vertigo, which are triggered by specific changes in the position of the head. BPPV is diagnosed from the characteristic symptoms and by observing the nystagmus such as in the Dix-Hallpike test. BPPV is treated with several canalith repositioning procedures. AVN is the second most common cause of peripheral vertigo. Its key symptom is the acute onset of sustained rotatory vertigo without hearing loss. It is treated with symptomatic therapy with antihistamines, anticholinergic agents, anti-dopaminergic agents, and gamma-aminobutyric acid-enhancing agents that are used for symptoms of acute vertigo. Meniere's disease is characterized by episodic vertigo, fluctuating hearing loss, and tinnitus. It is traditionally relieved with life-style modification, a low-salt diet, and prescription of diuretics. However, diagnosis and treatment of the peripheral vertigo can be difficult without knowledge of BPPV, AVN, and Meniere's disease. This article provides information on the differential diagnosis of peripheral vertigo in BPPV, AVN, and Meniere's disease.

• Korean Journal of Oriental Medicine
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• v.9 no.1
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• pp.157-178
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• 2003

Objective : This study was designed to assess the protective effects of Chengwhabosimtang on the animal model of depression, chronic mild stress(CMS). Method : Male Sprague-Dawley rats Were used for this experiment. The subjects Were divided into 3 groups (1. CMS-drug: Chengwhabosimtang administered during CMS treatment, 2. CMS-vehicle: water administered, 3. normal ). After 4 weeks of CMS treatment they were executed Forced swimming test(FST) and Elevated plus maze. Tyrosine hydroxylase(TH) in ventral tegmental area(VTA) and c-Fos in paraventricular nucleus(PVN) were measured. Result : 1. In FST, CMS-drug group showed significantly decreased immobility behavior. 2. CMS-drug group showed no significantly lower TH level in VTA than CMS-vehicle group. 3. CMS-drug group showed significantly less c-Fos expressed cell bodies in PVN than CMS-vehicle group. 4. In Elevated plus maze, CMS-drug group showed no significantly anxiety. Conclusion : These results suggest that Chengwhabosimtang may have protective antidepressant effects in CMS model rats. And these effects could be explained by the elevated stress-copying behaviors which are related with PVN of hypothalamus and dopaminergic neurons in VTA.

• Biomolecules & Therapeutics
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• v.26 no.5
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• pp.425-431
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• 2018

Cocaine- and amphetamine-regulated transcript (CART) peptide is a widely distributed neurotransmitter expressed in the central nervous systems. Previously, several reports demonstrated that nucleus accumbal-injected CART peptide positively modulated behavioral sensitization induced by psychostimulants and regulated the mesocorticolimbic dopaminergic pathway. It is confirmed that CART peptide exerted inhibitory effect on psychostimulant-enhanced dopamine receptors signaling, $Ca^{2+}$/calmodulin-dependent kinase signaling and crucial transcription factors expression. Besides modulation of dopamine receptors-related pathways, CART peptide also exhibited elaborated interactions with other neurotransmitter receptors, such as glutamate receptors and ${\gamma}$-aminobutyric acid receptors, which further account for attribution of CART peptide to inhibition of psychostimulant-potentiated locomotor activity. Recently, CART peptide has been shown to have anxiolytic functions on the aversive mood and uncontrolled drug-seeking behaviors following drug withdrawal. Moreover, microinjection of CART peptide has been shown to have an antidepressant effect, which suggests its potential utility in the mood regulation and avoidance of depression-like behaviors. In this review, we discuss CART pathways in neural circuits and their interactions with neurotransmitters associated with psychostimulant-induced depression.

• Archives of Pharmacal Research
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• v.26 no.12
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• pp.1074-1078
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• 2003

The effects of glycine on morphine-induced hyperactivity, reverse tolerance and postsynaptic dopamine receptor supersensitivity in mice was examined. A single administration of morphine (10 mg/kg, s.c.) induced hyperactivity as measured in mice. The morphine-induced hyperactivity was inhibited by pretreatment with glycine (100, 200 and 400 mg/kg, i.p.). In addition, it was found repeated administration of morphine (10 mg/kg, s.c.) to mice daily for 6 days caused an increase in motor activity which could be induced by a subsequent morphine dose, an effect known as reverse tolerance or sensitization. Glycine (100, 200 and 400 rng/kg, i.p.) also inhibited morphine-induced reverse tolerance. Mice that had received 7 daily repeated administrations of morphine also developed postsynaptic dopamine receptor supersensitivity, as shown by enhanced ambulatory activity after administration of apomorphine (2 mg/kg, s.c.). Glycine inhibited the development of postsynaptic dopamine receptor supersensitivity induced by repeated administration of morphine. It is suggested that the inhibitory effects of glycine might be mediated by dopaminergic (DAergic) transmission. Accordingly, the inhibition by glycine of the morphine-induced hyperactivity, reverse tolerance and dopamine receptor supersensitivity suggests that glycine might be useful for the treatment of morphine addiction.

• YAKHAK HOEJI
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• v.45 no.2
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• pp.205-213
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• 2001

The dopaminergic receptors were consisted of two distinct subtypes, $D_1$and $D_2$, each having different function. The present study was attempted to investigate the effects of R(-)-2,10,11-trihydroxy-N-n-propylnoraporphine (TNPA), a dopamine $D_2$receptor agonist, on renal function in dog. TNPA (5.0~15.0 $\mu$g/kg), when given into the vein, produced a dose-dependently antidiuresis along with the decrease in osmolar clearance ( $C_{osm}$) and urinary excretion of sodium and potassium ( $E_{Na}$ , and $E_{K}$). It also increased reabsorption rates of sodium and potassium in renal tubules ( $R_{Na}$ , $R_{K}$) without any changes in glomerular filtration rate (GFR), renal plasma flow (RPF) and free water clearance ( $C_{H2o}$). TNPA (0.5~1.5 $\mu$g/kg/min) infused into a renal artery decreased urine flow both in the experimental and the control kidneys. TNPA (1.5~5.0 $\mu$g/kg) administered via the carotid artery also greatly exhibited antidiuresis even at intravenously ineffective doses. Changes of renal function by TNPA given into both the renal artery and the carotid artery were almost the same aspect to those induced by intravenous TNPA. These results obtained from the present study suggest that TNPA produces antidiuresis by increasing the reabsorption rates of electrolytes in renal tubules, mainly distal tubule, through changing of central function.unction.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.40-40
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• 2003

Spontaneous firing rate and patterns of dopaminergic neurons in midbrain are key factors in determining the level of dopamine at target loci as well as in the mechanisms such as reward and motor coordination. Although glutamate, as a major afferent, is reported to enhance firing rate, the detailed actions of NMDA-, AMPA/kainate-, and metabotropic glutamate receptors (mGluR) on filing patterns are not clear. Thus we have investigated the role of glutamate receptors on the spontaneous firing activities using the network-free, acutely isolated dopamine neurons from substantia nigra pars compacta(SNc) of the 9-14 days rat. The isolated cells showed spontaneous regular firings of near 2.5 Hz, whose rate was enhanced by glutamate at submicromolar levels (0.3 $\square$M) but abolished by high concentrations more than 10 $\square$M.

• Journal of Korean Academy of Nursing
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• v.40 no.4
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• pp.580-588
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• 2010

Purpose: The purpose of this study was to examine effects of decreased locomotor activity on mass, Type I and II fiber cross-sectional areas of ipsilateral and contralateral hindlimb muscles 21 days after establishing the Parkinson's disease rat model. Methods: The rat model was established by direct injection of 6-hydroxydopamine (6-OHDA, 50 ${mu}g$) into the left substantia nigra after stereotaxic surgery. Adult male Sprague-Dawley rats were assigned to one of two groups; the Parkinson's disease group (PD; n=17) and a sham group (S; n=8). Locomotor activity was assessed before and 21 days after the experiment. At 22 days after establishing the rat model, all rats were anesthetized and soleus and plantaris muscles were dissected from both ipsilateral and contralateral sides. The brain was dissected to identify dopaminergic neuronal death of substantia nigra in the PD group. Results: The PD group at 21 days after establishing the Parkinson's disease rat model showed significant decrease in locomotor activity compared with the S group. Weights and Type I and II fiber cross-sectional areas of the contralateral soleus muscle of the PD group were significantly lower than those of the S group. Conclusion: Contralateral soleus muscle atrophy occurs 21 days after establishing the Parkinson's disease rat model.

• Journal of Sasang Constitutional Medicine
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• v.14 no.3
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• pp.153-159
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• 2002

Parkinson's disease(PD) is characterized by chronic progress of mesencephalic dopaminergic neuronal death. Diagnostic criteria for PD require at least two of three motor sign: tremor, rigidity, or bradykinesia. Levodopa and the dopamine agonists are considerd first-line drug therapy. In the book ‘dongyi soose bowon(東醫壽世保元)’, Soyangin Gihwangbeakho-tang(地黃白虎湯) is used at Soyangin Interior-overheated-disease. This case is patient who is 69 years old lady, suffered by the tremor of jaw and a slight rigidity, bradykinesia etc. This patient was classified as Soyangin by features, somatotype and emotional patterns. She improved in the tremor of jaw and others with Gihwangbeakho-tang for 67days. The result revealed that Soyangin-Gihwangbeakho-tang was effected on the tremor of jaw and others with Parkinson's disease patient.

• Animal cells and systems
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• v.10 no.3
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• pp.115-120
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• 2006

Parkinson's disease (PD) is a neurodegenerative disease caused by selective degeneration of dopaminergic neurons in the substantia nigra. Mutations in ${\alpha}$-synuclein have been causally linked to the pathogenesis of hereditary PD. In addition, it is a major component of Lewy body found in the brains of sporadic cases as well. In the present study, we examined whether overexpression of wild type or PD-related mutant ${\alpha}$-synuclein induces unfolded protein response (UPR) and triggers the known signaling pathway of the resulting endoplasmic reticulum (ER) stress in SH-SY5Y cells. Overexpression of wild type, A30P, and A53T ${\alpha}$-synuclein all induced XBP-1 mRNA splicing, one of the late stage UPR events. However, activation of ER membrane kinases and upregulation of ER or cytoplsmic chaperones were not detected when ${\alpha}$-synuclein was overexpressed. However, basal level of cytoplsmic calcium was elevated in ${\alpha}$-synuclein-expressing cells. Our observation suggests that overexpression of ${\alpha}$-synuclein induces UPR independent of the known ER membrane kinase-mediated signaling pathway and induces ER stress by disturbing calcium homeostasis.