• Korean Journal of Pharmacognosy
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• v.44 no.3
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• pp.281-285
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• 2013

Ethanol extract of Gastrodia elata fermented with Lactobacillus brevis was highly effective on the duration of pentobarbital hypnosis in mice. Pretreatment of mice with ethanol extract of the fermented Gastrodia elata (200 mg/kg, p.o.) prolonged markedly the duration of pentobarbital sleeping time and reduced the sleep latency. The mechanism of the extract of the fermented Gastrodia elata was investigated to inhibit the binding of $^3H$-Flumazenil, a selective benzodiazepine receptor antagonist, to benzodiazepine receptor of mice cortices. $IC_{50}$ value from displacement of $^3H$-Flumazenil binding was 62 ${\mu}g/mL$ at the treatment of the fermented Gastrodia elata. Therefore, these finding, such as increase of sleeping time and reduction of sleep latency, was examined by elevated concentration of GABA and parishin C, which were increased by Lactobacillus brevis.

• Journal of Life Science
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• v.25 no.5
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• pp.594-600
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• 2015

Protein-protein interactions have a critical role in the regulation of many cellular functions. Postsynaptic density-95/disks large/zonula occludens-1 (PDZ) domain is one of domains that mediate protein-protein interactions. PDZ domains typically bind to the specific motif at the carboxyl (C)-terminal end of partner proteins. Multi-PDZ domain protein 1 (MUPP1), which has 13 PDZ domains, serves a scaffolding function for structure proteins and signaling proteins, but the cellular function of MUPP1 has not been fully elucidated. We used the yeast two-hybrid system to identify proteins that interact with PDZ domains of MUPP1. We found an interaction between MUPP1 and muskelin. Muskelin was recently identified as a GABA_A receptor (GABA_AR) α1 subunit binding protein and known to have a role in receptor endocytosis and degradation. Muskelin bound to the 3^rd PDZ domain, but not to other PDZ domains of MUPP1. The C-terminal end of muskelin was essential for the interaction with MUPP1 in the yeast two-hybrid assay. When co-expressed in HEK-293T cells, muskelin but not the C-terminal deleted muskelin was co-immunoprecipitated with MUPP1. In addition, MUPP1 co-localized with muskelin at the same subcellular region in cells. These findings collectively suggest that MUPP1 or its interacting proteins could modulate GABA_AR trafficking and turnover through the interaction with muskelin.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.1
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• pp.241-246
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• 2003

Bambusae Caulis in Liquamen(BCL) has been used to relieve the cough and asthma, and remove the phlegm in traditional Oriental medicine. In recent years, it was studied for its antiinflammatory, antiallergenic, immune-modulating, and anticarcinogenic capabilities. This experiment was performed to evaluate the microarray profiles of CD genes in human mast cells before and after BCL treatment. The results are as follows: The expression of 51 of the genes studied was up-regulated in the Bel-treated group; they include the genes coding L apoferritin, beta-2-microglobulin, ferritin light polypeptide, CD63, monocyte chemotactic and activating fact, heme oxygenase 1, CD140a, integrin alpha M, colony stimulating factor 2 receptor, eukaryotic translation elongation factor, CD37, interleukin 18, NADH dehydrogenase 1 beta, CD48, 5-lipoxygenase activating protein, interleukin 4, ribosomal protein L5, GABA(A) receptor-associated protein, beta-tubulin, integrin beta 1, CD162, CD32, lymphotoxin beta, alpha-tublin, integrin alpha L, CD2, CD151, CD331, 90 kDa heat shock protein, CD59, CD3Z, microsomal glutathione S-transferase 2, CD33, CD162R, cyclophilinA, CD84, interleukin 9 receptor, interleukin 11, CD117, CD39-Like 2, and so forth. The expression of 7 of the genes studied was down-regulated in the BCL-treated group; they include the genes coding con, CD238, SCF, CD160, CD231, CD24, and CD130. Consequently, the treatment of BCL on the human mast cells increased the expression of 51 genes and decreased the expression of 7 genes. These data would provide a fundamental basis to the traditional applications of Bambusae Caulis in Liquamen.

• Biomolecules & Therapeutics
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• v.24 no.2
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• pp.115-122
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• 2016

Sleep, which is an essential part of human life, is modulated by neurotransmitter systems, including gamma-aminobutyric acid (GABA) and dopamine signaling. However, the mechanisms that initiate and maintain sleep remain obscure. In this study, we investigated the relationship between melatonin (MT) and dopamine D2-like receptor signaling in pentobarbital-induced sleep and the intracellular mechanisms of sleep maintenance in the cerebral cortex. In mice, pentobarbital-induced sleep was augmented by intraperitoneal administration of 30 mg/kg MT. To investigate the relationship between MT and D2-like receptors, we administered quinpirole, a D2-like receptor agonist, to MT- and pentobarbital-treated mice. Quinpirole (1 mg/kg, i.p.) increased the duration of MT-augmented sleep in mice. In addition, locomotor activity analysis showed that neither MT nor quinpirole produced sedative effects when administered alone. In order to understand the mechanisms underlying quinpirole-augmented sleep, we measured protein levels of mitogen-activated protein kinases (MAPKs) and cortical protein kinases related to MT signaling. Treatment with quinpirole or MT activated extracellular-signal-regulated kinase 1 and 2 (ERK1/2), p38 MAPK, and protein kinase C (PKC) in the cerebral cortex, while protein kinase A (PKA) activation was not altered significantly. Taken together, our results show that quinpirole increases the duration of MT-augmented sleep through ERK1/2, p38 MAPK, and PKC signaling. These findings suggest that modulation of D2-like receptors might enhance the effect of MT on sleep.

• Proceedings of the Korean Biophysical Society Conference
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• 1998.06a
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• pp.35-35
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• 1998

Catfish retina contains cone- and rod-horizontal cells. Only the cone-horizontal cell (cone-HC) has an axon and axon terminal. We compared the distribution of excitatory and inhibitory receptors in axon terminals and somata to begin to learn about the distinct functions of these two structures.(omitted)

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.8
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• pp.1091-1097
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• 2002

Capacitated goat spermatozoa generated diacyl glycerol (DAG) when suspended in Krebs-Ringer bicarbonate medium and induced by progesterone or $Ca^{2+}$ ionophore A23187. We have added Sn-1-oleoyl-2-acetyl glycerol externally, to study the effect of DAG in goat sperm acrosomal exocytosis. Addition of neomycin abolished the DAG generating capacity of progesterone in a dose dependent manner, suggesting the involvement of a phosphoinositidase C activated phospholipase C system in the process. The level of increase in phosphatidic acid was considerably low and was produced well after the DAG generation thereby suggesting the involvement of a DAG kinase which phosphorylates DAG to produce PA. The inhibition of progesterone mediated effect by inhibitors of $GABA_A/Cl^{-}$ channel and $Ca^{2+}$ channels further supports the evidence that the events of binding of agonist to the receptor(s), opening of $Ca^{2+}$ channels and the activation of phospholipase C are reconciled to perform the function of acrosome reaction in capacitated goat spermatozoa.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.2
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• pp.69-76
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• 2004

A variety of G protein coupled receptors (GPCRs) are expressed in the presynaptic terminals of central and peripheral synapses and play regulatory roles in transmitter release. The patch-clamp whole-cell recording technique, applied to the calyx of Held presynaptic terminal in brainstem slices of rodents, has made it possible to directly examine intracellular mechanisms underlying the GPCR-mediated presynaptic inhibition. At the calyx of Held, bath-application of agonists for GPCRs such as $GABA_B$ receptors, group III metabotropic glutamate receptors (mGluRs), adenosine $A_1$ receptors, or adrenaline ${\alpha}2$ receptors, attenuate evoked transmitter release via inhibiting voltage-activated $Ca^{2+}$ currents without affecting voltage-activated $K^+$ currents or inwardly rectifying $K^+$ currents. Furthermore, inhibition of voltage-activated $Ca^{2+}$ currents fully explains the magnitude of GPCR-mediated presynaptic inhibition, indicating no essential involvement of exocytotic mechanisms in the downstream of $Ca^{2+}$ influx. Direct loadings of G protein ${\beta}{\gamma}$ subunit $(G{\beta}{\gamma})$ into the calyceal terminal mimic and occlude the inhibitory effect of a GPCR agonist on presynaptic $Ca^{2+}$ currents $(Ip_{Ca})$, suggesting that $G{\beta}{\gamma}$ mediates presynaptic inhibition by GPCRs. Among presynaptic GPCRs glutamate and adenosine autoreceptors play regulatory roles in transmitter release during early postnatal period when the release probability (p) is high, but these functions are lost concomitantly with a decrease in p during postnatal development.

• Natural Product Sciences
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• v.23 no.1
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• pp.40-45
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• 2017

Epilepsy is a brain disorder that affects millions of people worldwide. It is characterized by recurrent and unpredictable seizures that are usually controlled with antiepileptic/anticonvulsive drugs. However, most antiepileptic drugs produce various side effects such as tolerance and sedation. Thus, there is a growing interest for alternative anticonvulsive drugs, preferably from natural or herbal sources. In this study, we evaluated the anticonvulsive effects of Rehmannia glutinosa (RG). The anticonvulsive effect of RG extract was evaluated using electroshock- and chemical-induced seizure tests in mice. To identify its probable mechanism of action, the effects of RG extract on $Cl^-$ influx was measured in vitro. We found that RG extract has anticonvulsive effects against electroshock-induced seizures, as indicated by an increased seizure threshold in mice. The RG extract also decreased the percentage of seizure responses induced by the GABAergic antagonist, pentylenetetrazole. These results suggest that the anticonvulsive effects of RG extract are mediated through a GABAergic mechanism. In support of this mechanism, our in vitro test showed that RG extract increases intracellular $Cl^-$ influx. Furthermore, RG extract did not show sedative and/or muscle relaxant effects in the open-field and rota-rod tests. Altogether, these results confirm that RG extract could be a herbal anticonvulsant and a potential alternative for clinical use.

• Journal of Life Science
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• v.20 no.1
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• pp.1-8
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• 2010

We recently reported the distributions of AMPA ($\alpha$-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate) receptor subtypes glutamate receptors (GluR) 1 and GluR4 in the superior colliculi (SC) of hamsters with antibody immunocytochemistry and the effect of enucleation on these distributions. We also compared these labelings to those of calcium-binding proteins calbindin D28K, calretinin, parvalbumin, and GABA. In the present study, we investigated whether the GluR1- and GluR4-immunoreactive (IR) neurons are interneurons or projection neurons by injection of the retrograde tracer horseradish peroxidase (HRP) into one of each major ascending and descending pathways of the SC. HRP injections were made into a tecto-reticulospinal pathway (TRS) and dorsal lateral geniculate nucleus (dLGN). Animals were then allowed to recover and to survive for 48 hr before perfusion. Sections containing retrograde-labeled neurons were then treated for GluR-immunoreactivity. HRP injections proved that only a small population of the GluR1-IR cells project into TRS (1.4%) and dLGN (2.6%). However, a large subpopulation of GluR4-IR cells project into TRS (32.7%). The differential compositions of inter/projection neurons, along with our previous studies on the separate distribution of the GluR subunits, its differential co-localization with calcium-binding proteins and GABA, and differential reactions to enucleations, strongly imply the functional variety of the receptor subunits in visual behavior responses.

• Biomolecules & Therapeutics
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• v.25 no.2
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• pp.112-121
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• 2017

Drug-induced liver injury (DILI) is the serious and fatal drug-associated adverse effect, but its incidence is very low and individual variation in severity is substantial. Acetaminophen (APAP)-induced liver injury accounts for >50% of reported DILI cases but little is known for the cause of individual variations in the severity. Intrinsic genetic variation is considered a key element but the identity of the genes was not well-established. Here, pre-biopsy method and microarray technique was applied to uncover the key genes for APAP-induced liver injury in mice, and a cause and effect experiment employing quantitative real-time PCR was conducted to confirm the correlation between the uncovered genes and APAP-induced hepatotoxicity. We identified the innately and differentially expressed genes of mice susceptible to APAP-induced hepatotoxicity in the pre-biopsied liver tissue before APAP treatment through microarray analysis of the global gene expression profiles (Affymetrix $GeneChip^{(R)}$ Mouse Gene 1.0 ST for 28,853 genes). Expression of 16 genes including Gdap10, Lpl, Gabra3 and Ccrn4l were significantly different (t-test: FDR <10%) more than 1.5 fold in the susceptible animals than resistant. To confirm the association with the susceptibility to APAP-induced hepatotoxicity, another set of animals were measured for the expression level of selected 4 genes (higher two and lower two genes) in the liver pre-biopsy and their sensitivity to APAP-induced hepatotoxicity was evaluated by post hoc. Notably, the expressions of Gabra3 and Lpl were significantly correlated with the severity of liver injury (p<0.05) demonstrating that these genes may be linked to the susceptibility to APAP-induced hepatotoxicity.