• The Korean Journal of Zoology
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• v.33 no.3
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• pp.247-254
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• 1990

Chicken monocular head and eye optokinetic nystagmus (OKN) were observed by coil recordings after intravitreal administration of GABA antagonists (picrotoxin and bicuculline) into the opened and closed eye. Before injection of drugs the chicken displayed an OKN for T-N stimulation being more efficient in evoking this visuomotor reflex than for N-T stimulation. The injection of GABA antagonist into the opened eye provoked a decrease or disappearance of the head and eye OKN. On the other hand, the injection of GABA antagonist into the closed eye, the head and eye OKN augmented. Thus, GABA antagonist abolished the directional asymmetry of the head and eye OKN, indicating the involvement of GABAergic mechanisms in the inhibition of the N-T component of the monocular OKN.

• YAKHAK HOEJI
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• v.36 no.5
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• pp.496-505
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• 1992

The correlation between GABA receptors($GABA_A$ and $GABA_B$ receptor) and benzodiazepine receptor on the saline infusion-induced micturition reflex contraction was studied in the female rat. To investigate the effect of ${\gamma}-aminobutyric$ acid(GABA) on the micturition reflex, exogenous GABA(10 mg/kg) and GABA transaminase inhibitor(aminooxyacetic acid; AOAA $1\;{\mu}g$) were administered intravenously(i.v.) and intracerebroventriculary(i.c.v.), respectively. In result, both GABA and AOAA inhibited the saline induced micturition reflex contraction. This AOAA induced inhibition of micturition reflex was blocked by both bicuculine. $GABA_A$ receptor antagonist, and Ro 15-1788, benzodiazepine receptor antagonist. Muscimol, $GABA_A$ receptor antagonist($0.1\;{\mu}g$ i.c.v., $3\;{\mu}g$ intrathecal; i.t., 1 mg/kg i.v.) and baclofen, $GABA_A$ receptor agonist($1\;{\mu}g$ i.c.v., $3\;{\mu}g$ i.t., 1 mg/kg i.v.) also inhibited the bladder contraction. Pretreatment of bicuculline($1\;{\mu}g$ i.c.v.), but not of 5-aminovaleric acid(AVA, $1\;{\mu}g$ i.c.v.), $GABA_B$ receptor antagonist blocked the central inhibition of muscimol. These inhibitory effects were reversed by Ro15-1788 but were potentiated by flurazepam, benzodiazepine receptor antagonist. On the other hand, the inhibitory effects of baclofen were not affected by Ro 15-1788. Diazepam and flurazepam also inhibited the micturition reflex contraction when they were administered $3\;{\mu}g$ i.c.v., $10\;{\mu}g$ i.t., $10\;{\mu}M$, $30\;{\mu}M$ transurethrally, respectively. In conclusion, these results suggest that the micturition reflex is mediated by $GABA_A$, $GABA_B$ receptor and benzodiazepine receptor. The bezodiazepines increase the receptor binding of GABA to the $GABA_A$ receptor, so that the benzodiiazepines show the synergistic effect on the inhibition of the micturition reflex contraction, but not to the $GABA_B$ receptor.

• Biomolecules & Therapeutics
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• v.13 no.3
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• pp.138-142
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• 2005

Adenosine and GABA are known to be major inhitory neurotransmitters in the central nervous system and its receptors mediate various neurophamacological effects including cardiovascular modulatory effects. Inhibitory cardiovascular effects induced by intrathecal (i.t.) administration of adenosine $A_1$ receptor agonist and its modulation by cyclic AMP was suggested by our previous report. In this experiment, we examined the modulation of cardiovascular effects of adenosine $A_1$ receptor and adenosine $A_2$ receptor by $GABA_B$ receptors antagonist in the spinal cord. I.t. administration of 10 nmol of $N^6$-cyclohexyladenosine (CHA, an adenosine $A_1$ receptor agonist), I.t. administration of 2 nmol of 5'-(N-cyclopropyl)-carboxamidoadenosine (CPCA, an adenosine $A_2$ receptor agonist), pretreatment with 5-aminovaleric acid (a $GABA_B$ receptor antagonist, 50 nmol, i.t.) prior to administration of CHA and pretreatment with 5-aminovaleric acid (a $GABA_B$ receptor antagonist, 50 nmol, i.t.) prior to administration of CPCA were performed in anesthetized, artificially ventilated Sprague-Dawley rats. I.t. administration of 50 nmol of 5-aminovaleric acid significantly attenuated the inhibitory cardiovascular effects of CHA but did not attenuated the inhibitory cardiovascular effects of CPCA. It is suggested that cardiovascular responses of adenosine $A_1$ receptor is modulated by $GABA_B$ receptor and adenosine $A_2$ receptor is not modulated by $GABA_B$ receptor in the spinal cord.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.7
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• pp.1087-1095
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• 2020

Objective: The present study aimed to evaluate the effects of γ-aminobutyric acid (GABA)-producing bacteria (GPB) on in vitro rumen fermentation and on the growth performance and meat quality of Hanwoo steers. Methods: The effects of GPB (Lactobacillus brevis YM 3-30)-produced and commercially available GABA were investigated using in vitro rumen fermentation. Using soybean meal as a substrate, either GPB-produced or commercially available GABA were added to the in vitro rumen fermentation bottles, as follows: control, no additive; T1, 2 g/L GPB; T2, 5 g/L GPB; T3, 2 g/L autoclaved GPB; T4, 5 g/L autoclaved GPB; T5, 2 g/L GABA; and T6, 5 g/L GABA. In addition, 27 Hanwoo steers (602.06±10.13 kg) were subjected to a 129-day feeding trial, during which they were fed daily with a commercially available total mixed ration that was supplemented with different amounts of GPB-produced GABA (control, no additive; T1, 2 g/L GPB; T2, 5 g/L GPB). The degree of marbling was assessed using the nine-point beef marbling standard while endotoxin was analyzed using a Chromo-Limulus amebocyte lysate test. Results: In regard to in vitro rumen fermentation, the addition of GPB-produced GABA failed to significantly affect pH or total gas production but did increase the ammonia nitrogen (NH₃-N) concentration (p<0.05) and reduce total biogenic amines (p<0.05). Animals fed the GPB-produced GABA diet exhibited significantly lower levels of blood endotoxins than control animals and yielded comparable average daily gain, feed conversion ratio, and beef marbling scores. Conclusion: The addition of GPB improved in vitro fermentation by reducing biogenic amine production and by increasing both antioxidant activity and NH₃-N production. Moreover, it also reduced the blood endotoxin levels of Hanwoo steers.

• Natural Product Sciences
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• v.13 no.4
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• pp.384-389
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• 2007

Treatment of mice with Korean Red Ginseng (KRG) changed glutamic acid and GABA content in the mouse brain tissue with pentylenetetrazole (PTZ)-induced convulsion. KRG were orally administered at a dose of 50, 100 mg/kg for two weeks. The electroconvulsions (MES) and PTZ-induced convulsion were reduced but those induced by strychnine, bicuculine and picrotoxin were not. PTZ-induced convulsion decreased the $\~{a}$-aminobutyric acid (GABA) content in brain compared to control group while the content was increased in KRG-treated group compared to PTZ group. In the PTZ-treated group, the GABA-transaminase (GABA-T) activity was increased by 59.6%, while no effect was observed on glutamate decarboxylase (GAD) activity. These results support that the KRG decreased the GABA contents and modulated the glutamic acid contents in the brain.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.3
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• pp.567-571
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• 2002

In order to prove the sedative, anticonvulsive effects of Incenses and to identify the effect of this medicine to cerebral glutamic acid and GABA density in experimental animal. we used Incense which was made of traditional herb medicines. We also examined what kind of material is to be involved in biosynthesis of these elements. In addition we experimented to find out synthesis of active GABA-T. Incenses were inhaled 8 hours a day for 4 weeks to mice. Finally we have following results. On the convulsion induced by pentylenetetrazole(PTZ), Incenses showed significant anticonvulsive effect. Density of glutamic acid in brain was significantly decreased. On the contrary, density of GABA was significantly increased. The Activity of GABA- T in brain was significantly reduced. The quantity of lipid peroxide in the brain was significantly decreased. Activity of xanthine oxidase and aldehyde oxidase were significantly reduced in brain. From the above results, we confirmed that Incenses decreased the density of glutamic acid, increased GABA density and decreased the activity of GABA- T in brain. For the convulsion which was induced by PTZ, Incenses showed significant anticonvulsive effect. With this we can recognize that Incenses had ability to control the quantity of lipid peroxide in brain. In the conclusion, Incenses has significant anticonvulsive effect, so I strongly recommend to prescribe Incenses to treat convulsive disorder like epilepsy.

• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.710-716
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• 2016

Gamma-aminobutyric acid (GABA) is a non-protein amino acid, which is an important inhibitor of neurotransmission in the human brain. GABA is also used as the precursor of biopolymer Nylon-4 production. In this study, the carbon flux from the tricarboxylic acid cycle was directed to the GABA shunt pathway for the production of GABA from glucose. The GABA shunt enzymes succinate-semialdehyde dehydrogenase (GabD) and GABA aminotransferase (GabT) were co-localized along with the GABA transporter (GadC) by using a synthetic scaffold complex. The co-localized enzyme scaffold complex produced 0.71 g/l of GABA from 10 g/l of glucose. Inactivation of competing metabolic pathways in mutant E. coli strains XBM1 and XBM6 increased GABA production 13% to reach 0.80 g/l GABA by the enzymes co-localized and expressed in the mutant strains. The recombinant E. coli system developed in this study demonstrated the possibility of the pathway of the GABA shunt as a novel GABA production pathway.

• Journal of Chest Surgery
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• v.31 no.5
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• pp.441-450
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• 1998

The medullospinal tract cells are known to play an important role in the control of the cardiovascular activities. To clarify the modes of action of the neurotransmitters on these cells, glutamate, GABA(${\gamma}$-aminobutyric acid) and bicuculline were applicated iontophoretically into the rostral ventrolateral medulla in adult cats anesthetised with ${\alpha}$-chloralose. Followings are the results obtained : 1. The spontaneous activities of the cardiac-related neurons in rostral ventrolateral medulla (RVLM) were increased by the glutamate and decreased by the GABA. 2. Bicuculline, an antagonist of GABA, alone didn't increase the frequency of the action potentials, but could reverse the cellular response to the GABA, simultaneously applicated. 3. GABA seemed to decrease the peak as well as the basal discharge of the neurons in RVLM, but hardly changed their periodicities. 4. The cellular responses of RVLM evoked by the peripheral nerve stimulation could be inhibited by the iontophoretically released GABA. In conclusion, GABA seemed to act as an inhibitory neurotransmitter on the cardiac- related neurons in RVLM of the cats anesthetized with ${\alpha}$-chloralose. But the maintenance of the periodicities of these cells after the application of bicuculline suggested that the afferent activity of the baroreceptor didn't play a key role in the spontaneous activities of the RVLM neurons.

• Korean Journal of Pharmacognosy
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• v.31 no.1
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• pp.23-27
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• 2000

The effect of seventy kinds of medicinal plants on the activities of GABA-metabolizing enzymes as glutamate dehydrogenase I (GDH I), glutamate dehydrogenase II (GDH II), GABA transaminase (GABA-T), succinic semialdehyde dehydrogenase (SSADH) and succinic semialdehyde reductase (SSAR) were estimated. The following plants extracts from Acori graminei Rhizoma, Longnae Arillus, Gastrodiae Herba, Lycii Fructus, Ligusticum officinale, Ferula assafoetida, Corydalis Tuber, Eucommiae Cortex, Zizyphi spinosi Semen activated the activity of GDH I to more than 35%, and the following ones from Visci Ramulus, Ligusticum officinale, Myristicae Semen, Ferulae Resina, Scolopendrae Corpus, Corydalis Tuber, Eucommiae Cortex, Zizyphi spinosi Semen did that of GDH II. The plant extracts from Cynanchi Radix, Astragali Semen, Angelicae dahuricae Radix, Biotae orientalis Folium, Uncariae Ramulus et Uncus, Polygalae Radix, Cynomorii Herba inhibited that of GABA-T to 35% and over, and the following ones from Hyoscyamus niger, Cynanchi Radix, Acori graminei, Caesalpiniae Lignum, Cannabis Semen, Sedum aizoon, Sedum kamtschaticum, Schisandrae Fructus, Lilii Bulbus, Biotae orientalis Folium, Uncariae Ramulus et Uncus, Myristicae Semen, Akebiae Fructus, Cynomorii Herba, Buddleiae Flos, Mucunae Caulis, Zizyphi Fructus, Paeoniae Radix rubra did that of SSADH to 70% and over; the following ones from, Caesalpiniae Lignum, Sedum kamtschaticum, Schisandrae Fructus, Astragali Semen, Angelicae dahuricae Radix, Dioscorea nipponica, Myristicae Semen, Akebiae Fructus, Cynomorii Herba, Scutellariae Radix did that of SSAR.

• Journal of Oriental Neuropsychiatry
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• v.10 no.2
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• pp.85-103
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• 1999

In order to prove the anticonvulsive effect of the fragrance of Magnoliae Flos in convulsion-induced mice, experiments were performed on anticonvulsive effect, GABA level, glutamic acid level, GABA-T activity and GAD activity. The results were obtained as follows: 1. As far as anticonvulsive effect was concerned, on the convulsion induced by such as maximal electric seizure, strychnine, bicuculline, or picrotoxin it was not significant, but the convulsion induced by pentylenetetrazole it was significant comparing to the control group. 2. GABA level was increased significantly in mice. 3. Glutamic acid level was decreased significantly in mice. 4. GABA-T activity was decreased by the fragrance of Magnoliae Flos. 5. The fragrance of Magnoliae Flos was not effective in GAD activity. From above result, the fragrance of Magnoliae Flos had significant effects on convulsion induced by pentylenetetrazole, so it is expected to clinical application on convulsive diseases such as epilepsy.