• The Korean Journal of Physiology and Pharmacology
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• v.5 no.6
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• pp.479-485
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• 2001

The existence of opioid receptors in mammalian cerebellum except human, has not been clearly understood. In the present study, we found that NPY was inducible by morphine in the mouse cerebellar granular and Purkinje cell layers. We performed in situ RT-PCR and immunohistochemistry to characterize the NPY expression. The increase of NPY gene expression by morphine (30 mg/kg, i.p.) was inhibited by pretreatment with not only naloxone (100 mg/kg, i.p.) but also a noncompetitive NMDA antagonist, MK-801 (0.3 mg/kg, i.p.). The competitive NMDA antagonist, AP-5 (0.9 mg/kg, i.p.) slightly attenuated the increased NPY expression by morphine. Also, the finding similar to morphine was shown by NMDA (70 mg/kg, i.p.) treatment. Our results indicate that NPY was inducible by morphine and this might reflect activation of NMDA receptors in granule cells that relay mossy fiber inputs to Purkinje cells via parallel fibers.

• Journal of Genetic Medicine
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• v.18 no.1
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• pp.55-59
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• 2021

West syndrome (WS) presenting with infantile spasms, developmental delay, and hypsarrhythmia has genetic etiology in some patients. Movement disorders or visual impairment that share genetic underpinnings with infantile spasms can provide diagnostic clues for specific genetic mutations. Mutations of the GRIN1 gene encoding the glutamate receptor inotropic N-methyl-D-aspartate subunit can result in WS with hyperkinetic movements, cortical visual impairment, autistic features, and bilateral polymicrogyria. An 11-month-old boy with WS showed hyperkinetic movements and visual impairment. Brain magnetic resonance imaging and metabolic investigations revealed no abnormalities. Whole-exome sequencing revealed a novel likely pathogenic variant (c.1561_1563del; p.Asn521del) of GRIN1 (NM_007327.3). The proband was treated with vigabatrin and became seizure-free within one week. Notably, the cortical blindness improved within 3 months and the hyperkinetic movements resolved one year after the proband became seizure-free. To the best of our knowledge, this is the first report of GRIN1 encephalopathy in Koreans.

• Journal of Life Science
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• v.25 no.9
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• pp.1043-1050
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• 2015

Glutamate is one of the principle transmitters in the CNS. Ionotropic receptors of glutamate, selectively activated by N-methyl-D-aspartate (NMDA), play an important role in the processes of cell development, learning, memory, and etc. On the other hand, many studies discovered that over-activation of glutamate receptors leads to neurodegeneration and are known to be implicated in major areas of brain pathology. Any sustained effect of a transient NMDA receptor activation is likely to involve signaling to the nucleus and to trigger coordinated changes in gene expression. Classically, a set of immediate-early genes are induced first; some of genes are by themselves transcription factors that control expression of other target genes. This study provides understanding of changes of inducible transcription factors mRNA levels with RT-PCR by inducing over-activation of NMDA receptor with intraperitoneal NMDA injection. The experimental conditions were varied by 1, 5, 25, and 125 g/ of body weight NMDA and measured transcription factors mRNA levels are Egr-1, c-Jun, JunB, and FosB. Based on result obtained, inducible transcription factors mRNA in NMDA injection to mice with 5 g/body weight showed the greatest change. And ITF mRNA showed greatest change 24 hr after injection. The expression level of JunB mRNA was markedly changed. Up to the present days, no study clearly understood how ITF mRNA affected the apoptosis of purkinje cells in the cerebellum. The current study improves the understanding of the mechanism of apoptosis of purkinje cells in the cerebellum.

• Biomolecules & Therapeutics
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• v.30 no.3
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• pp.232-237
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• 2022

Autism spectrum disorder (ASD) having core characteristics of social interaction problems and repetitive behaviors and interests affects individuals at varying degrees and comorbidities, making it difficult to determine the precise etiology underlying the symptoms. Given its heterogeneity, ASD is difficult to treat and the development of therapeutics is slow due to the scarcity of animal models that are easy to produce and screen with. Based on the theory of excitation/inhibition imbalance in the brain with ASD which involves glutamatergic and/or GABAergic neurotransmission, a pharmacologic agent to modulate these receptors might be a good starting point for modeling. N-methyl-D-aspartic acid (NMDA) is an amino acid derivative acting as a specific agonist at the NMDA receptor and therefore imitates the action of the neurotransmitter glutamate on that receptor. In contrast to glutamate, NMDA selectively binds to and regulates the NMDA receptor, but not other glutamate receptors such as AMPA and kainite receptors. Given this role, we aimed to determine whether NMDA administration could result in autistic-like behavior in adolescent mice. Both male and female mice were treated with saline or NMDA (50 and 75 mg/kg) and were tested on various behavior experiments. Interestingly, acute NMDA-treated mice showed social deficits and repetitive behavior similar to ASD phenotypes. These results support the excitation/inhibition imbalance theory of ASD and that NMDA injection can be used as a pharmacologic model of ASD-like behaviors.

• Korean Journal of Biological Psychiatry
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• v.13 no.4
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• pp.289-298
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• 2006

Objectives : Autism is a complex neurodevelopmental spectrum disorder with a strong genetic component. Previous neurochemical and genetic studies suggested the possible involvement of glutamate N-methyl-D-aspartate(NMDA) receptor in autism. The aim of study was to investigate the association between the NMDA2B receptor gene(GRIN2B) and autism spectrum disorders(ASD) in the Korean population. Methods : The patients with ASD were diagnosed with Autism Diagnostic Interview-Revised and Autism Diagnostic Observation Schedule based on DSM-IV diagnostic classification. The present study was conducted with the detection of four single nucleotide polymorphisms(SNPs) in GRIK2 and family-based association analysis of the single nucleotide polymorphisms in Korean ASD trios using transmission disequilibrium test (TDT). Results : One hundred twenty six patients with ASD and their biological parents were analyzed. 86.5% were male and 85.1% were diagnosed as autistic disorder. The mean age was $71.9{\pm}31.6$ months(range : 26-185 months). We found that rs1805247 showed significantly preferential transmission(TDT ${\chi}^2$=12.8, p<0.001) in ASD. Conclusion : One SNP in GRIN2B gene was significantly associated with ASD in the Korean population. This result suggests the possible involvement of glutamate NMDA receptor gene in the development of ASD.

• Journal of Veterinary Clinics
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• v.23 no.4
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• pp.393-399
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• 2006

Ketamine, one of general anesthetics for human and veterinary use, is a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist which interferes with the action of excitatory amino acids. It has been reported to impair various leukocyte functions. In this study, the effect of ketamine on the oxidative burst activity (OBA) of canine peripheral blood leukocytes was examined. The OBA of canine peripheral blood phagocytes was analyzed by flow cytometry system. Ketamine at higher concentration such as $1,000{\mu}M$ exhibited a low viability of leukocytes. Thus, ketamine was used at concentration of 10 to $500{\mu}M$ showing no cytotoxic effect and high cell viability. The OBA of leukocytes in the presence or absence of latex beads was analyzed by addition of dihydrorhodamine 123. The direct treatment of ketamine revealed the inhibitory effect on the OBA of peripheral blood polymorphonuclear cells (PMN) and monocyte-rich cells but not peripheral blood mononuclear cells (PBMC) in the presence of latex beads. However, when latex beads were not added to PMN, its OBA was not inhibited by ketamine. The OBA of PMN and monocyte-rich cells but not PBMC in the presence of latex beads was also inhibited by culture supernatant from ketamine-treated- PBMC but not -PMN. But the OBA of PMN in the absence of latex beads was not inhibited by culture supernatant from PBMC treated with ketamine. Therefore, these results suggested that ketamine has the inhibitory effect on the OBA of canine peripheral blood phagocytes such as neutrophils and monocytes during phagocytic response.

• Journal of Life Science
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• v.27 no.3
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• pp.355-360
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• 2017

Consumption of high doses of ethanol can lead to amnesia, which often manifests as a blackout. This incoordination of blackout may be a major cause in various social problems in alcohol consumption. However, there is still no treatment for preventing these alcohol-induced problems. Hydrangeae dulcis folium is a drug or a tea which is made from the fermented and dried leaves of Hydrangea serrata Seringe. The present study, we tested the ethanol extract of the Hydrangeae dulcis folium (EHDF) on ethanol-induced psychological deficits. To test behavioral deficits, an object recognition test was conducted using a mouse model. To evaluate synaptic deficits, N-methyl-D-aspartate (NMDA) receptor-mediated excitatory postsynaptic potential EPSP and long-term potentiation (LTP) in the mouse hippocampal slices were tested, as they are known to be vulnerable to ethanol and are associated with ethanol-induced amnesia. In the tests, ethanol (1 g/kg, i.p.) impaired object recognition memory, but EHDF (10 or 30 mg/kg) prevented this impairment in object recognition test. Interestingly, EHDF ($30{\mu}g/ml$) significantly ameliorated ethanol-induced LTP and NMDA receptor-mediated synaptic transmission in the hippocampal slices. EHDF prevented ethanol-induced object recognition memory deficits induced by ethanol. Interestingly, EHDF significantly ameliorated ethanol-induced LTP and NMDA receptor- mediated synaptic transmission in the hippocampal slices.

• Korean Journal of Medicinal Crop Science
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• v.24 no.5
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• pp.375-385
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• 2016

Background: The study was conducted to elucidate the extraction conditions under which white ginseng has cognition-improving efficacy. Methods and Results: Extracts from white ginseng under different solvent and temperature conditions were analyzed for ginsenoside content and inhibitory effect on N-methyl-D-aspartate (NMDA) receptor and acetylcholinesterase. The total ginsenoside contents and amounts of ginsenoside Rb1 plus ginsenoside Rg1 from the 1st extracts (prepared with EtOH/$H_2O$ as solvent) were higher than those from the 2nd extracts (extracted with $H_2O$ after the 1st EtOH/$H_2O$ extraction). The contents in the 1st and 2nd extracts produced at $80^{\circ}C$ were also higher than those obtained at $50^{\circ}C$. Samples from the 1st extraction at $80^{\circ}C$ indicated higher inhibitory activities on NMDA receptors-whose excessive activation is thought to mediate the calcium-dependent neurotoxicity associated with several neurodegenerative diseases-than those from the 2nd extraction. Among the samples prepared at varying temperatures, the extract prepared at $50^{\circ}C$ showed the highest suppression activity on NMDA receptors. Note, however, that the extracts from the 2nd extraction at $50^{\circ}C$ inhibited acetylcholinesterase-whose inhibition could be a therapeutic strategy for neurodegenerative diseases with cognitive deficits and memory malfunction-more effectively than those from the 1st extraction. Conclusions: To enhance the cognition-improving activity of white ginseng extract, it is suggested that the extracts be utilized after being combined the 1st extracts (made with EtOH/$H_2O$ solvent) and the 2nd extracts (prepared with $H_2O$) at low temperature.

• Korean Journal of Psychosomatic Medicine
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• v.29 no.2
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• pp.207-212
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• 2021

Anti-N-methyl-D-aspartate receptor (Anti-NMDAR) encephalitis is a neuroinflammatory disease mediated by autoantibodies to NMDAR. In the initial clinical stages of anti-NMDAR encephalitis, psychiatric symptoms like delusions, perceptual disturbances, and disorganized speech or behaviors are pronounced even without obvious neurological symptoms. Early treatments like immunotherapy and/or tumor removal are central to good clinical outcomes. Hence, it is important to diagnose early anti-NMDAR encephalitis, distinguishing it from mental disorder. In the present case study, the authors described psychiatric symptoms assessed with Positive and Negative Syndrome Scale (PANSS) of Ms. A, a 26-year-old woman, in the early phase of anti-NMDAR encephalitis. We will discuss the characteristic psychopathology of anti-NMDAR encephalitis toward prompt diagnosis and treatment. Ms. A showed a higher negative subscale score than positive one on the PANSS. Compared with mental disorder, negative symptoms and cognitive impairment would be more prominent in the early stage of anti-NMDAR encephalitis. Rituximab and teratoma removal were effective, and quetiapine showed good tolerability. It is recommended to evaluate anti-NMDAR encephalitis when negative symptoms, cognitive impairment, catatonia, changes in consciousness level, and neurological symptoms are observed, especially in young women.

• Korean Journal of Medicinal Crop Science
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• v.27 no.2
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• pp.115-125
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• 2019

Background: Glycyrrhiza radix (licorice root) have been used as an oriental medicine material for long time, and its protective effects on oxidative stress, inflammation and cognition deficit have been recently reported. However, the cultivation of Glycyrrhiza species as medicinal crops is associated with some problems such as low productivity and early leaf fall, etc. To resolve this problems, Glycyrrhiza cultivars have been developed by direct hybridization of each Glycyrrhiza species by Korean researchers. The present study was conducted to compare the Glycyrrhiza cultivar radix (Dagam, Sinwongam and Wongam) for their anti-oxidation, anti-inflammation, and cognition improvement effects and levels of liquiritin, isoliquiritigenin and licochalcone in order to select an excellent cultivar as a material resource. Methods and Results: For evaluating the inhibitory efficacies of the Glycyrrhiza cultivar extracts on oxidative stress and inflammation in BV2 cells, we measured their reactive oxygen species (ROS) production and nitric oxide (NO) release after treating them with lipopolysccharide. The scavenging activities on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and peroxynitrite ($NOO^-$) radicals were evaluated. Cell proliferation and N-methyl-D-aspartate receptor (NMDAR) inhibition were analyzed. The total phenol, liquiritin, isoliquiritigenin and licochalcone A content in the extracts of the three culivars were quantified. Furthermore, the correlation coefficient between the activities and contents of total phenol, liquiritin, isoliquiritigenin and licochalcone A were also calculated. The results indicated that Sinwongam exhibited potent anti-oxidant, anti-inflammatory and NMDAR inhibititory activities. Sinwongam also showed higher total phenol and licochalcone A contents than the other cultivars. Among the three cultivars, Dagam exhibited a positive effects on NO release inhibition, cell proliferation and contents of liquiritin and isoliquiritigenin. Conclusions: Sinwongam is expected to be the most useful resource as a functional material for anti-oxidation/anti-inflammation and cognition improvement among the three studied licorice cultivars.