• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.4
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• pp.645-653
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• 2003

Taste receptor cells respond to gustatory stimuli using a complex arrangement of receptor molecules, signaling cascades and ion channels. When stimulated, these cells produce action potentials that result in the release of neurotransmitter onto an afferent nerve fiber that in turn relays the identity and intensity of the gustatory stimuli to tie brain. A variety of mechanisms are used in transducing the four primary tastes. Direct interaction of the stimuli with ion channels appears to be of particular importance in transducing stimuli reported as salty or sour, whereas tile second messenger systems cyclic AMP and inositol trisphosphate are important in transducing bitter and sweet stimuli. In addition to the four basic tastes, specific mechanisms exist for the amino acid glutamate, which is sometimes termed the fifth primary taste. The emerging picture is that not only do individual taste qualities use more than one mechanism, but multiple pathways are available for individual tastants as well.

• Journal of Oriental Physiology
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• v.14 no.2 s.20
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• pp.55-66
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• 1999

The effects of Bogi, Boyang and Onri herbs on glutamate receptor using nystatin perforated patch clamp under voltage clamp were investigated and the following results was obtained. Ginseng radix and Astragali radix were chosen as Bogi herbs. Cervi cornu and Boshniakiae herba were used as Boyang herbs. Aconiti tuber and Zingiberis rhizoma were selected as Onri herbs. 1. $10^{-6}M$ of glycine brought about the increase of the ion currents by Astragali radix. Cervi cornu. Boshniakiae herba and Aconiti tuber to a minute extent that has no experimental meaning. 2. It was assumed that Bogi herb had no effect on glutamate receptor since the ion currents of Ginseng radix and Astragali radix that are Bogi herbs had not been inhibited to a great extent by D-AP5 and CNQX. 3. Boyang herbs were seem to have meaningful relationship with non-NMDA receptor since the ion currents by Cervi cornu and Boshniakiae that are Boyang herbs were inhibited by CNQX but not inhibited to a meaningful extent by D-AP5. 4. D-AP5 had not a significant effect on the ion currents activated by Onri herbs such as Aconiti tuber and Zingiberis rhizoma. CNQX had a significant effect on the ion currents of Aconiti tuber but no effect on the ion currents of Zingiberis rhizoma. Therefore, it seemed that Aconiti tuber had a relationship with non-NMDA receptor while Zingiberis rhizoma had no relationship with glutamate receptor. In summary, Bogi, Boyang and Onri herbs had different effects through different mechanisms on glutamate receptor. Hence it was believed that. through experiments on acetylcholine receptor new classification could be made.

• Journal of Integrative Natural Science
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• v.9 no.2
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• pp.128-135
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• 2016

5-hydroxytryptamine (serotonin) receptor ($5-HT_7R$) 7 is one of G-Protein coupled receptors, which is activated by the neurotransmitter Serotonin. After activation by serotonin, $5-HT_7$ activates the production of the intracellular signaling molecule cyclic AMP. $5-HT_7$ receptor has been found to be involved in the pathophysiology of various disorders. It is reported that $5-HT_7$ receptor antagonists can be used as antidepressant agents. In this study, we report the important structural and chemical parameters for 2-methoxyphenylpiperazinylakanamides as $5-HT_7R$ inhibitors. A 3D QSAR study based on comparative molecular field analysis (CoMFA) was performed. The best predictions were obtained for the best CoMFA model with $q^2$ of 0.594 with 6 components, $r^2$ of 0.986, Fisher value as 60.607, and an estimated standard error of 0.043. The predictive ability of the test set was 0.602. Results obtained the CoMFA models suggest that the data are well fitted and have high predictive ability. The contour maps are generated and studied. The contour analyses may serve as tool in the future for designing of novel and more potent $5-HT_7R$ derivatives.

• Biomedical Science Letters
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• v.18 no.3
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• pp.218-226
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• 2012

Dopamine is an enteric neurotransmitter that regulates gastrointestinal motility. This study was done to investigate whether dopamine modulates spontaneous pacemaker activity in cultured interstitial cells of Cajal (ICCs) from mouse using whole cell patch clamp technique, RT-PCR and live $Ca^{2+}$ imaging analysis. ICCs generate pacemaker inward currents at a holding potential of -70 mV and generate pacemaker potentials in current-clamp mode. Dopamine did not change the frequency and amplitude of pacemaker activity in small intestinal ICCs. On the contrary dopamine reduced the frequency and amplitude of pacemaker activity in large intestinal ICCs. RT-PCR analysis revealed that Dopamine2 and 4-receptors are expressed in c-Kit positive ICCs. Dopamine2 and 4 receptor agonists inhibited pacemaker activity in large intestinal ICCs mimicked those of dopamine. Domperidone, dopamine2 receptor antagonist, increased the frequency of pacemaker activity of large intestinal ICCs. In $Ca^{2+}$-imaging, dopamine inhibited spontaneous intracellular $Ca^{2+}$ oscillations of ICCs. These results suggest that dopamine can regulate gastrointestinal motility through modulating pacemaker activity of large intestinal ICCs and dopamine effects on ICCs are mediated by dopamine2 receptor and intracellular $Ca^{2+}$ modulation.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.2
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• pp.166-171
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• 2007

GABA is primary an inhibitory neurotransmitter that is localized in inhibitory interneurons. GABA is released from presynaptic terminals and functions by binding to GABA receptors. There are two types of GABA receptors, $GABA_{A}-receptor$ that allows chloride to pass through a ligand gated ion channel and $GABA_{B}-receptor$ that uses G-proteins for signaling. The $GABA_{A}$-receptor has a GABA binding site as well as a benzodiazepine binding sites, which modulate $GABA_{A}$-receptor function. Benzodiazepine GABAA receptor imaging can be accomplished by radiolabeling derivates that activates benzodiazepine binding sites. There has been much research on flumazenil (FMZ) labeled with $^{11}C-FMZ$, a benzodiazepine derivate that is a selective, reversible antagonist to GABAA receptors. Recently, $^{18}F-fluoroflumazenil$ (FFMZ) has been developed to overcome $^{11}C's$ short half-life. $^{18}F-FFMZ$ shows high selective affinity and good pharmacodynamics, and is a promising PET agent with better central benzodiazepine receptor imaging capabilities. In an epileptic focus, because the GABA/benzodiazepine receptor amount is decreased, using $^{11}C-FMZ$ PET instead of $^{18}F-FDG$ PET, restrict the foci better and may also help find lesions better than high resolution MR. $GABA_{A}$ receptors are widely distributed in the cerebral cortex, and can be used as an viable neuronal marker. Therefore it can be used as a neuronal cell viability marker in cerebral ischemia. Also, GABA-receptors decrease in areas where neuronal plasticity develops, therefore, $GAB_{A}$ imaging can be used to evaluate plasticity. Besides these usages, GABA receptors are related with psychological diseases, especially depression and schizophrenia as well as cerebral palsy, a motor-related disorder, so further in-depth studies are needed for these areas.

• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.68-68
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• 1999

Extracellular A TP is known to function as a neurotransmitter and as a modulator in the variety of cell types. In PC12 cells, extracellular A TP elevates [Ca$\^$2＋/]j through receptor-operated Ca$\^$2＋/ channels and through the activation of phospholipase C, thereby facilitating the secretion of neurotransmitters.(omitted)

• Proceedings of the Korean Biophysical Society Conference
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• 1997.07a
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• pp.11-12
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• 1997

A concept that extracellular ATP plays a role as a neurotransmitter is now widely accepted. ATP released from nerve terminals transmits both excitatory and inhibitory signals to postsynaptic neurons, muscle cells, and non-excitable cells. ATP-activated channels are effectors that convert the binding of ATP into the opening of ion channel pores in postsynaptic membrane.(omitted)

• Korean Journal of Exercise Nutrition
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• v.25 no.4
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• pp.38-44
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• 2021

[Purpose] Exercise can prevent conditions such as atrophy and degenerative brain diseases. However, owing to individual differences in athletic ability, exercise supplements can be used to improve a person's exercise capacity. Schisandra chinensis (SC) is a natural product with various physiologically active effects. In this study, we analyzed SC using a pharmacological network and determined whether it could be used as an exercise supplement. [Methods] The active compounds of SC and target genes were identified using the Traditional Chinese Medicine Database and Analysis Platform (TCMSP). The active compound and target genes were selected based on pharmacokinetic (PK) conditions (oral bioavailability (OB) ≥ 30%, Caco-2 permeability (Caco-2) ≥ -0.4, and drug-likeness (DL) ≥ 0.18). Gene ontology (GO) was analyzed using the Cytoscape software. [Results] Eight active compounds were identified according to the PK conditions. Twenty-one target genes were identified after excluding duplicates in the eight active compounds. The top 10 GOs were analyzed using GO-biological process analysis. GO was subsequently divided into three representative categories: postsynaptic neurotransmitter receptor activity (53.85%), an intracellular steroid hormone receptor signaling pathway (36.46%), and endopeptidase activity (10%). SC is related to immune function. [Conclusion] According to the GO analysis, SC plays a role in immunity and inflammation, promotes liver metabolism, improves fatigue, and regulates the function of steroid receptors. Therefore, we suggest SC as an exercise supplement with nutritional and anti-fatigue benefits.

• Korean Journal of Biological Psychiatry
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• v.20 no.4
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• pp.129-135
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• 2013

Aggression can be defined as 'behavior intended to harm another' which can be seen both from humans and animals. However, trying to understand aggression in a simplistic view may make it difficult to develop an integrated approach. So, we tried to explain aggression in a multidisciplinary approach, affected by various factors such as neuroanatomical structures, neurotransmitter, genes, and sex hormone. Parallel with animal models, human aggression can be understood with two phenomena, offensive aggression and defensive aggression. Neurobiological model of aggression give a chance to explain aggression with an imbalance between prefrontal regulatory influences and hyper-reactivity of the subcortical areas involved in affective evaluation, finally in an aspect of brain organization. Serotonin and GABA usually inhibit aggression and norepinephrine while glutamate and dopamine precipitate aggressive behavior. As there is no one gene which has been identified as a cause of aggression, functions between gene to gene interaction and gene to environment interaction are being magnified. Contributions of sex hormone to aggression, especially molecular biologic interaction of testosterone and regulation of estrogen receptor have been emphasized during the research on aggression. This multidisciplinary approach on aggression with types, neurochemical bases, and animal models can bring integrated interpretation on aggression.

• International Journal of Oral Biology
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• v.44 no.2
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• pp.50-54
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• 2019

Melatonin is a neurotransmitter that modulates various physiological phenomena including regulation and maintenance of the circadian rhythm. Nicotinic acetylcholine receptors (nAChRs) play an important role in oral functions including orofacial muscle contraction, salivary secretion, and tooth development. However, knowledge regarding physiological crosstalk between melatonin and nAChRs is limited. In the present study, the melatonin-mediated modulation of nAChR functions using bovine adrenal chromaffin cells, a representative model for the study of nAChRs, was investigated. Melatonin inhibited the nicotinic agonist dimethylphenylpiperazinium (DMPP) iodide-induced cytosolic free $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) increase and norepinephrine secretion in a concentration-dependent manner. The inhibitory effect of melatonin on the DMPP-induced $[Ca^{2+}]_i$ increase was observed when the melatonin treatment was performed simultaneously with DMPP. The results indicate that melatonin inhibits nAChR functions in both peripheral and central nervous systems.