• 대한약리학회지
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• 제28권1호
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• pp.1-9
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• 1992

최근에 개발된 생체내 미세투석법을 이용하여 정상혈압 흰쥐(WKY)와 자연발생성 고혈압 흰쥐(SHR)의 후 시상하부에서 세포외액의 모노아민과 그 대사체들을 측정하였다. 뇌정위 고정장치에 의해서 미세투석관을 후 시상하부에 위치시킨후 링거액으로 관류하였다. 모노아민과 그 대사체들은 고속액체 크로마토그라피와 전기화학 검출기를 이용하여 정량하였다. 미세투석관의 시험관내 회수율 검사 결과, 관류액의 유속과 신경화학물질의 상대적 회수율 사이에는 역비례 관계가 있음이 확인되었다. 정상 혈압 흰쥐에서 후 사상하부의 관류액으로 부터 축정한 각종 신경화학물질의 세포외액 농도는 도파민 32nM, 노르에피네프린 50nM, 에피네프린 50nM, 세로토닌 73nM, 3.4-dihydroxyphenylacetic acid(DOPAC) 281 nM, homovanillic acid(HVA) 181 nM, 5-hydroxyindoleacetic acid(5HIAA) 3767nM이었다. 후 시상하부에서 측정된 신경전달물질의 기준치는 WHY와 SHR사이에 차이가 없었으나, DOPAC, HVA, 5HIAA의 기준치는 WKY에 비해서 SHR에서 유의하게 높게 나타났다. 본 연구는 중추 신경화학물질들의 생체내 측정에 미세투석법을 이용할 수 있음을 보여주었다.

• The Korean Journal of Physiology and Pharmacology
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• 제6권1호
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• pp.9-14
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• 2002

In the present study, we used the microdialysis technique combined with high performance liquid chromatography (HPLC) and electrochemical detection to measure the extracellular levels of norepinephrine (NE) in the posterior hypothalamus in vivo, and to examine the effects of various drugs, affecting central noradrenergic transmission, on the extracellular concentration of NE in the posterior hypothalamus. Microdialysis probes were implanted stereotaxically into the posterior hypothalamus (coordinates: posterior 4.3 mm, lateral 0.5 mm, ventral 8 mm, relative to bregma and the brain surface, respectively) of rats, and dialysate collection began 2 hr after the implantation. The baseline level of monoamines in the dialysates were determined to be: NE $0.17{\pm}0.01,$ 3,4-dihydroxyphenylacetic acid (DOPAC) $0.94{\pm}0.07,$ homovanillic acid (HVA) $0.57{\pm}0.05$ pmol/sample (n=8). When the posterior hypothalamus was perfused with 90 mM potassium, maximum 555% increase of NE output was observed. Concomitantly, this treatment significantly decreased the output of DOPAC and HVA by 35% and 28%, respectively. Local application of imipramine $(50\;{\mu}M)$ enhanced the level of NE in the posterior hypothalamus (maximum 200%) compared to preperfusion control values. But, DOPAC and HVA outputs remained unchanged. Pargyline, an irreversible monoamine oxidase inhibitor, i.p. administered at a dose of 75 mg/kg, increased NE output (maximum 165%), while decreased DOPAC and HVA outputs (maximum 13 and 12%, respectively). These results indicate that NE in dialysate from the rat posterior hypothalamus were neuronal origin, and that manipulations which profoundly affected the levels of extracellular neurotransmitter had also effects on metabolite levels.

• 대한수의학회지
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• 제38권3호
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• pp.535-543
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• 1998

In the present study, we designed and constructed new microdialysis probe in order to improve the efficacy and accuracy of microdialysis method. In addition, extracellular concentrations of GABA, glutamate, aspartate and glycine were monitored with new designed probe in the lateral portion of the ventrocaudal periaqueductal gray using unanesthetized and unrestrained rats. Furthermore, the effect of opiates on release of these amino acids, especially GABA, was analyzed by measuring their concentration in PAG dialysates following veratridine administration in the presence of systemic morphine. The results were summerized as follow : 1. The damaging rates of 1.0mm or 1.5mm window probe were 12.5% or 42.8%, respectively. In the group using 1.5mm window probe, the damaging area was extended into mesencephalic aqueduct because of microdialyzing pressure. 2. Because of the unique design of our probes with an opening facing one side, dialysis occurs in a hemisphere($600{\mu}m$ in mediolateral direction and $100{\mu}m$ in opposite side of the dialysis probe) around the opening rather than in a spherical shaped configuration which is typical of most commercially available probe designs. 3. Glutamate, taurine and glycine were present in the highest concentration in the dialysate sample obtained before treatment with veratridine, whereas, aspartate and GABA were present in the lowest concentration. 4. The concentration of all 5 amino acids increased significantly following $75{\mu}m$ veratridine perfusion into lateral ventrocaudal PAG. 5. There was no significant difference between basal and peak amino acid concentrations according to window sizes. 6. Morphine had no effect on baseline concentrations of amino acids in dialysates obtained from the lateral PAG as compared to saline treated controls. However, following veratridine treatment, morphine selectively affected GABA release in the lateral ventrocaudal PAG as compared to saline treated controls. These results suggest that GABAergic interneurons in the PAG are inhibited by opioids. Therefore, endogenous enkephalins or endorphins may directly inhibit intrinsic GABAergic intemeurons and block their tonic inhibition of PAG-NMR projection neurons. Moreover, new designed probes demonstrate improved efficiency and accuracy in collecting samples as compared to commercial types of microdialysis probes.

• 동의생리병리학회지
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• 제18권5호
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• pp.1322-1330
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• 2004

This experimental studies were performed in order to prove the effect of Phospholipase A₂(PLA₂) Herbal-acupuncture by using rats that had neuronal damage due to the Middle Cerebral Artery Occulsion(MCAO). We observed the change of extracellular concentrations(μM) Of dopamine, DOPAC, HVA, HIAA, glutamate, aspartate, GABA, glysine, taurine, alanine, and tyrosine as extracted by vivo microdialysis, in the PLA₂ Herbal-acupuncture administrated rats(240-260g, Sprague-Dawley) subjected to the MCAO. The dialysates were extracted three times before the MCAO and six times after the MCAO every 20 minutes, and ana lysed by highperformance liquid chromatography(HPLC). PLA₂ Herbal-acupuncture significantly inhibited glutamate and tyrosine which are stimulant neurotransmitters at brain ischemia, and it significantly decreased glycine, GABA, taurine, and alanine which are inhibitory neurotransmitters at brain ischemia. PLA₂ Herbal-acupuncture may prevent delayed neuronal death(DND) in selectively vulnerable focal areas of the brain effectively.

• 대한약침학회지
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• 제7권2호
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• pp.29-41
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• 2004

Objective : This experimental studies were performed in order to prove the effect of Hirudin Herbal-acupuncture by using rats that had neuronal damage due to the Middle Cerebral Artery Occulsion(MCAO). Method : We observed the change of extracellular concentrations(${\mu}M$) of dopamine, DOPAC, HVA, HIAA, glutamate, aspartate, GABA, glysine, taurine, alanine, and tyrosine as extracted by vivo microdialysis, in the Hirudin Herbal-acupuncture administrated rats($240{\sim}260g$, Sprague-Dawley) subjected to the MCAO. The dialysates were extracted three times before the MCAO and six times after the MCAO every 20 minutes, and analysed by highperformance liquid chromatography(HPLC). Results : Hirudin Herbal-acupuncture significantly inhibited glutamate, aspartate, and tyrosine which are stimulant neurotransmitters at brain ischemia, and it significantly decreased glycine, GABA, taurine, and alanine which are inhibitory neurotransmitters at brain ischemia. Conclusion : Hirudin Herbal-acupuncture may prevent delayed neuronal death(DND) in selectively vulnerable focal areas of the brain effectively.

• Applied Biological Chemistry
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• 제44권3호
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• pp.148-152
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• 2001

본 연구에서는 유기인제에 의한 뇌 손상유발에 있어서 흥분성 아미노산계의 역할을 규명하고자 하였다. Djisopropylfluorophosphate(DFP)를 투여하여 뇌 손상을 유발한 흰쥐에 있어서, 뇌 해마부위에서의 aspartate 및 glutamate의 농도를 측정함으로써 경련유발에 따른 신경전달계의 변화와, 이에 따른 신경조직의 변화를 관찰하였다. 치료약물로 항콜린 약물인 atropine과 NMDA 수용체 길항제인 procyclidine을 각각 단독 또는 병합 투여하여 DFP에 의한 뇌신경독성에 대한 방어효과를 관찰하였다. DFP를 투여한 흰쥐는 경련유발과 더불어 해마부위 에서의 현저한 aspartate와 glutamate의 농도 증가를 보였으며, 병리조직학적으로 해마의 신경세포 감소를 보였다. DFP에 의하여 상승되어진 해마부위의 aspartate와 glutamate의 수준은 procyclidine에 의하여 현저히 억제 되었으나, atropine에 의하여는 DFP 투여군과 유의한 차이를 보이지 않았다. Procyclidine과 atropine 병합 투여 시에는 procyclidine 단독 투여시와 동일한 효과를 관찰할 수 있었다. 조직염색소견에서도 DFP에 의하여 현저하게 소실되어진 신경세포는 atropine 단독 투여시보다 procyclidine 단독 투여군 또는 atrpopine과 procyclidine 병합 투여군에서 뚜렷한 신경세포의 손상 및 소실을 방어하는 것을 관찰할 수 있었다. 따라서 DFP에 의하여 유발된 경련은 흥분성 아미노산 신경전달계를 활성화시키고 이에 따라 뇌신경의 손상이 유발되는 것으로 생각된다. 특히 procyclidine은 DEP에 의한 경련유발과 뇌 세포손상을 효과적으로 방어할 수 있었으며, 이는 흥분성 아미노산계 중 NHDA수용체가 DFP에 의한 뇌 손상기전에 관여됨을 시사한다. 이상의 결과로 DFP에 의하여 유발된 경련은 일차적으로 콜린성 신경계를 과도하게 자극하여 이에 따른 흥분성 아미노산의 과도한 분비를 유발하고 특히 NMDA 수용체를 활성화하여 뇌의 손상을 가져온다고 사료된다.

• 동의생리병리학회지
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• 제19권4호
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• pp.982-992
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• 2005

Acupuncture as a therapeutic intervention is widely used for the treatment of many functional disorders such as substance abuse and mental dysfunction. Clinical trials are currently underway to determine the effectiveness of acupuncture in the treatment of drug addiction. Yet, there are still many unanswered questions about the basic mechanism of acupuncture. Studies have shown that both the psychomotor stimulant effects and rewarding properties of addictive drugs, including morphine, are sensitized by repeated drug administration and raised the possibility that both of these effects may De linked to the same or closely overlapping the mesolimbic dopamine systems. Neiguan (PC6) point on the pericardium channel which is associated with the brain and its mental function, has been used to treat mental, psychosomatic disorders and gastroenterological disorders. The present study was designed to investigate the effect of acupuncture on repeated morphine-induced changes in extracellular dopamine levels using in vivo microdialysis and to measure the effect of acupuncture on repeated morphine-induced behavioral changes. Male Sprague-Dawley rats were treated twice a day for three days with increasing doses of morphine (10, 20 and 40 mg/kg, s.c.) or with saline. After 15 days of withdrawal, rats were challenged with morphine hydrochloride (5 mg/kg, s.c.). Acupuncture was applied at bilateral Neiguan (PC6) points for 1min after the morphine challenge. Results showed that acupuncture at the specific acupoint PC6, but not at control points (tail and HE8) significantly decreased both dopamine release, behavior induced by a systemic morphine challenge or a single s.c. morphine injection in the morphine-repeated animals. These results suggest that reduction in sensitization may be one mechanism whereby acupuncture alleviates morphine craving in addicts. Moreover, in a more general sense these results suggest that acupuncture can be used as a therapeutic intervention for correcting reversible malfunction of the body by direction of brain pathway and thus acupuncture can contribute to the biochemical balance in the central nervous system by regulating neurotransmitters.

• 동의신경정신과학회지
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• 제16권2호
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• pp.13-24
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• 2005

Background and Objectives : Acupuncture as a therapeutic intervention is widely used for the treatment of many functional disorders such as substance abuse and mental dysfunction. Clinical trials are currently underway to determine the effectiveness of acupuncture in the treatment of drug addiction. Yet, there are still many unanswered questions about the basic mechanism of acupuncture. Studies have shown that both the psychomotor stimulant effects and rewarding properties of addictive drugs, including morphine, are sensitized by repeated drug administration and raised the possibility that both of these effects may be linked to the same or closely overlapping the mesolimbic dopamine systems. Neiguan (PC6) point on the pericardium channel which is associated with the brain and its mental function, has been used to treat mental, psychosomatic disorders and gastroenterological disorders. The present study was designed to investigate the effect of acupuncture on repeated morphine-induced changes in extracellular dopamine levels using in vivo microdialysis and to measure the effect of acupuncture on Fos-like immunoreactivity. Methods : Male Sprague-Dawley rats were treated twice a day for three days with increasing doses of morphine (10, 20 and 40 mg/kg, s.c.) or with saline. After 15 days of withdrawal, rats were challenged with morphine hydrochloride (5 mg/kg, s.c.). Acupuncture was applied at bilateral Neiguan (PC6) points for 1 min after the morphine challenge. Results showed that acupuncture at the specific acupoint PC6, but not at control points (tail and HE8) significantly decreased Fos-like immunoreactivity induced by a systemic morphine challenge or a single s.c. morphine injection in the morphine-repeated animals. Results and Conclusions : These results suggest that reduction in sensitization may be one mechanism whereby acupuncture alleviates morphine craving in addicts. Moreover, in a more general sense these results suggest that acupuncture can be used as a therapeutic intervention for correcting reversible malfunction of the body by direction of brain pathway and thus acupuncture can contribute to the biochemical balance in the central nervous system by regulating neurotransmitters.