• Journal of Ginseng Research
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• v.36 no.4
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• pp.403-410
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• 2012

The current inquiry was conducted to assess the change in sleep architecture after long periods of administration to determine whether ginseng can be used in the therapy of sleeplessness. Following post-surgical recovery, red ginseng extract (RGE, 200 mg/kg) was orally administrated to rats for 9 d. Data were gathered on the 1st, 5th, and 9th day, and an electroencephalogram was recorded 24 h after RGE administration. Polygraphic signs of unobstructed sleep-wake activities were simultaneously recorded with sleep-wake recording electrodes from 11:00 a.m. to 5:00 p.m. for 6 h. Rodents were generally tamed to freely moving polygraphic recording conditions. Although the 1st and 5th day of RGE treatment showed no effect on power densities in nonrapid eye movement (NREM) and rapid eye movement (REM) sleep, the 9th day of RGE administration showed augmented ${\alpha}$-wave (8.0 to 13.0 Hz) power densities in NREM and REM sleep. RGE increased total sleep and NREM sleep. The total percentage of wakefulness was only decreased on the 9th day, and the number of sleep-wake cycles was reduced after the repeated administration of RGE. Thus, the repeated administration of RGE increased NREM sleep in rats. The ${\alpha}$-wave activities in the cortical electroencephalograms were increased in sleep architecture by RGE. Moreover, the levels of both ${\alpha}$- and ${\beta}$-subunits of the ${\gamma}$-aminobutyric acid $(GABA)_A$ receptor were reduced in the hypothalamus of the RGE-treated groups. The level of glutamic acid decarboxylase was over-expressed in the hypothalamus. These results demonstrate that RGE increases NREM sleep via $GABA_A$ergic systems.

• Journal of Life Science
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• v.29 no.5
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• pp.564-569
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• 2019

Heavy drinking disrupts the nervous system by activation of GABA receptors and inhibition of glutamate receptors, thereby preventing short-term memory formation. Degradation of cognition by alcohol induces blackouts, and it can lead to alcoholic dementia if repeated. Therefore, drugs need to be developed to prevent alcohol-induced blackout. In this study, we confirmed the effect of an ethanol extract of Cassia obtusifolia seeds (COE) on alcohol-induced memory impairment. The effects of COE and ethanol on cognitive functions mice were examined using the passive avoidance and Y-maze tests. The manner in which alcohol affects long-term potentiation (LTP) in relation to the learning and memory was confirmed by electrophysiology performed on mouse hippocampal slices. We also measured N-methyl-D-aspartate (NMDA) receptor-mediated field excitatory synapses (fEPSPs), which have a known association with cognitive impairment caused by ethanol. Ethanol caused memory impairments in passive avoidance and Y-maze tests. COE prevented these ethanol-induced memory impairments in these tests. Ethanol also blocked LTP induction in the mouse hippocampus, and COE prevented this ethanol-induced LTP deficit. Ethanol decreased NMDA receptor-mediated fEPSPs in the mouse hippocampus, and this decrease was prevented by COE. These results suggest that COE might be useful in preventing alcohol-induced neurological dysfunctions, including blackouts.

• Biomedical Science Letters
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• v.27 no.2
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• pp.69-76
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• 2021

The aim of this study was to evaluate gamma-aminobutyric acid (GABA)-induced erythropoietin (EPO) and EPO-receptor expression in human Hep3B cells and Sprague Dawley (SD) rats during hypoxia. Expression levels of EPO, EPO-R mRNA, Janus kinase-2 (JAK-2), vascular endothelial growth factor (VEGF), hypoxia inducible factor-1 (HIF-1), and HIF-2 in response to GABA treatment were evaluated in cell lines. SD rats were randomly divided into 5 groups of 8 rats each, and GABA was orally administered; the groups were the normal control (NC), hypoxia-exposed (G0), as well as the GABA 1 mg/100 g body weight (BW) GABA treated group (G1), 5 mg/100 g BW GABA treated group (G5), and 10 mg/100 g BW GABA treated group (G10) with hypoxia. We analyzed EPO levels and red blood cell counts in rat blood and EPO gene expression in kidney tissue. EPO and VEGF mRNA levels in Hep3B cells exposed to hypoxia were significantly increased and further increased after GABA treatment. However, the expression of EPO-R and JAK-2 mRNAs were not affected by GABA, but hypoxia-induced HIF-1 and HIF-2 mRNA expression was inhibited by GABA. In the kidney tissue of rats exposed to hypoxia, the expression level of EPO mRNA was greatly increased, but levels in the GABA treatment groups significantly decreased. EPO levels in the serum showed the same significant trend, but the red blood cell counts were not significantly different. These findings demonstrate that HIF-1 and HIF-2 activation increase EPO expression in Hep3B cells exposed to hypoxia. However HIF decreased by GABA addition and VEGF increased significantly.

• Journal of Life Science
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• v.28 no.5
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• pp.597-604
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• 2018

Although the core mechanisms of Attention Deficit/Hyperactivity Disorder (ADHD) are unknown, several ADHD-associated proteins have been studied. G-protein - coupled receptor kinase interacting protein-1 (GIT1) is a multifunctional adapter protein that affects neuron growth and dendrite formation. GIT1-deficient mice have shown ADHD-like behavior and also recovered through amphetamine treatment. In this study, gliotransmitters were investigated in both intracellular and extracellular space from GIT1-deficient mice. To measure the amount of gliotransmitters, primary astrocyte cultures were taken from the cerebral and cerebellar cortices of wild (WT), hetero (HE), and knock-out (KO) mice. Major gliotransmitters were analyzed using high-performance liquid chromatography. It was observed that the amount of excitatory and inhibitory gliotransmitters were dependent on genotype and showed a change in excitation/inhibition ratios. Interestingly, the major excitatory gliotransmitter, glutamate, existed at the lowest level in WT mice, but the amount of inhibitory gliotransmitters, gamma-aminobutyric acid (GABA) and glycine, varied depending on brain region. Remarkably, an increased amount of GABA was measured at the intracellular cerebrum in WT mice compared with KO mice. It was presumed that KO mice would secrete more inhibitory gliotransmitters to compensate for GIT1 depletion or else acquire a defect to reuptake-secreted GABA. This may be a possible mechanism for ADHD pathology.

• Journal of Pharmaceutical Investigation
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• v.35 no.3
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• pp.193-199
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• 2005

Gabapentin is an antiepileptic drug that is structurally similar to ${\gamma}-aminobutyric$ acid (GABA), but does not interact with the GABA receptor. It does not bind significantly to plasma proteins, and is excreted to unchanged form in the urine. The purpose of the present study was to evaluate the bioequivalence of two gabapentin capsules, $Neurontin^{TM}$ capsule 300 mg (Pfizer Pharm. Co., Ltd.) and Kuhnil $Gabapentin^{TM}$ capsule 300 mg (Kuhnil Pharm. Co., Ltd), according to the guidelines of the Korea Food and Drug Administration (KFDA). The release of gabapentin from the two gabapentin formulations in vitro was tested using KP VIII Apparatus II method with various dissolution media (pH 1.2, 4.0, 6.8 buffer solution and water). Twenty six healthy male subjects, $22.46{\pm}1.86$ years in age and $67.64{\pm}7.24$ kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After a single capsule containing 300 mg as gabapentin was orally administered, blood samples were taken at predetermined time intervals and the concentrations of gabapentin in serum were determined using HPLC with fluorescence detector. The dissolution profiles of two formulations were similar at all dissolution media. In addition, the pharmacokinetic parameters such as $AUC_t$, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t$, $C_{max}$ and untransformed $T_{max}$. The results showed that the differences between two formulations based on the reference drug, $Neurontin^{TM}$ capsule 300 mg, were -2.03, -0.43 and 4.29% for $AUC_t$, $C_{max}$ and $T_{max}$, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log 0.8 to log 1.25 $(e.g.,\;log\;0.89{\sim}log\;1.09\;and\;log\;0.91{\sim}log\;1.09$ for $AUC_t$ and $C_{max}$, respectively). Thus, the criteria of the KFDA bioequivalence guideline were satisfied, indicating Kuhnil $Gabapentin^{TM}$ capsule 300 mg was bioequivalent to $Neurontin^{TM}$ capsule 300 mg.