• 대한수의학회지
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• 제32권2호
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• pp.165-173
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• 1992

The present study was carried out to investigate the effects of dopaminergic drugs and the role of specific dopamine(DA) receptors on the release of TSH, $T_4$ and $T_3$. Serum TSH levels (cold-induced, $4{^{\circ}C}$) were determined using RIA(radioimmunoassay) at 30 min after administration of dopamine agonists and antagonists. Serum $T_4$ and $T_3$ levels were detected after these dopaminergic drugs were administered subcutaneously twice a day for a week. The results of the study are summarized as follows : Apomorphine, a nonspecific DA receptor agonist, produced a dose-depedent decrease in serum TSH, $T_4$ and $T_3$ levels. However, only low doses (0.3, 1.0mg/kg) of SKF38393, a specific $D_1$-receptor agonist, produced a decrease in serum lelvels of TSH. I,Y171555, a specific $D_2$-receptor agonist, produced a dose dependent decrease in serum TSH, $T_4$ and $T_3$ levels. However, SCH23390, a specific $D_1$-receptor antagonist, produced a decrease except in serum T levels which were increased dose dependently. High doses (1.0, 3.0mg/kg) of sulpiride, a specific $D_2$-receptor antagonist, made a increase in the serum levels of TSH and $T_3$. The effects of dopaminergic drugs in serum TSH and $T_4$ levels was potentiated by the pretreatment of apomorphine. The overall results of this study suggest that the regulation of TSH, $T_4$ and $T_3$ secretion were mediated via specific $D_1$ and $D_2$ receptor.

• 대한핵의학회지
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• 제25권1호
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• pp.1-5
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• 1991

• BMB Reports
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• 제46권11호
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• pp.519-526
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• 2013

Dopamine (DA) regulates emotional and motivational behavior through the mesolimbic dopaminergic pathway. Changes in DA signaling in mesolimbic neurotransmission are widely believed to modify reward-related behaviors and are therefore closely associated with drug addiction. Recent evidence now suggests that as with drug addiction, obesity with compulsive eating behaviors involves reward circuitry of the brain, particularly the circuitry involving dopaminergic neural substrates. Increasing amounts of data from human imaging studies, together with genetic analysis, have demonstrated that obese people and drug addicts tend to show altered expression of DA D2 receptors in specific brain areas, and that similar brain areas are activated by food-related and drug-related cues. This review focuses on the functions of the DA system, with specific focus on the physiological interpretation and the role of DA D2 receptor signaling in food addiction.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1995년도 춘계학술대회
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• pp.101-101
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• 1995

The effects of ginseng prepation, Adaptagen$\^$R/ (AD), on the central dopaminergic nervous system in the learning-impaired rats were studied. The learning impaired rats were rendered by the intracerebroventricular infusion of ethylcholine aziridium (AF64A), 3 nmol/each side. Three days after the infusion of AF64A, AD were orally intubated daily for five days, 200 mg/kg. The control groups were intubated with distilled water. Twenty four hours after the last intubation, The changes in the specific bindings of dopamine receptors, the concentrations of dopamine (DA) and metabolites, The activities of tyrosine hydrosylase (TH) and monoamine oxidase (MAO) were analyzed using receptor radiography, HPLC-ECD and the methods in enzyme-assays, respectively.

• The Korean Journal of Physiology and Pharmacology
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• 제26권5호
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• pp.307-312
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• 2022

It is well known that dopamine transmission from the ventral tegmental area (VTA) modulates motivated behavior and reinforcement learning. Although dopaminergic neurons are the major type of VTA neurons, recent studies show that a significant proportion of the VTA contains GABAergic and type 2 vesicular glutamate transporter (VGLUT2)-positive neurons. The non-dopaminergic neurons are also critically involved in regulating motivated behaviors. Some VTA neurons appear to co-release two different types of neurotransmitters. They are VGLUT2-DA neurons, VGLUT2-GABA neurons and GABA-DA neurons. These co-releasing neurons show distinct features compared to the neurons that release a single neurotransmitter. Here, we review how VTA cell populations wire to the other brain regions and how these projections differentially contribute to motivated behavior through the distinct molecular mechanism. We summarize the activities, projections and functions of VTA neurons concerning motivated behavior. This review article discriminates VTA cell populations related to the motivated behavior based on the neurotransmitters they release and extends the classical view of the dopamine-mediated reward system.

• 대한약리학회지
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• 제18권2호
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• pp.103-117
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• 1982

신장기능 조절에 있어서 중추의 dopaminergic system의 역할을 구명하고자 dopamine의 선택적 길항제인 haloperidol을 가토의 측뇌실내로 투여하여 신장기능의 변동을 관찰하였다. Haloperidol 15와 $50{\mu}g/kg$투여시 항이뇨작용을 나타냈으며, $15{\mu}g/kg$의 경우는 주로 세뇨관에서 Na재흡수의 촉진에 의하였으며, $50{\mu}g/kg$의 경우에는 주로 세뇨관에서의 수분재흡수가 뚜렷하였다. 그러나 $150{\mu}g/kg$의 경우에서는 뚜렷한 이뇨작용을 볼 수 있었으며 이때 신혈류 및 사구체 여과율에는 유의한 변동을 볼 수 없었으나 세뇨관에서 Na재흡수가 현저히 억제되어 natriuresis 및 kaliuresis 가 출현되었다. 한편 dopamine은 5, 15, 50, $150{\mu}g/kg$의 양을 측뇌실내로 투여하였을때 투여랑에 대체로 비례하는 항이뇨효과를 관찰할 수 있었다. 여기에서 5, $15{\mu}g/kg$의 소량에 의하여는 그 항이뇨작용이 주로 신세뇨관에 있어서 Na재흡수의 촉진에 기인하였으나 $50{\mu}g/kg$이사의 양에서는 그 외에도 신혈류 및 사구체 여과율의 감소가 더욱 뚜렷하여짐을 볼 수 있었다. Haloperidol $150{\mu}g/kg$ 투여후에 dopamin을 투여하였을 때 $15{\mu}g/kg$ dopamine의 효과는 감퇴되었으나, 50, $150{\mu}g/kg$ dopamin의 항이뇨효과는 차단되지 아니하였으며 dopamine양의 증가에 따라 haloperidol의 이뇨작용이 소실됨을 볼 수 있었다. 이상의 실험결과는 대량의 haolperidol은 중추의 dopamine receptor에 대한 상경적 길항에 의하여 이뇨작용을 나타낸 것으로 해석되며, 소량의 haloperidol은 dopaminergic neurone에 있는 autoreceptor의 차단작용의 결과 항이뇨 작용이 나타난 것으로 추측되었다.

• 대한약리학회지
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• 제30권1호
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• pp.11-18
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• 1994

Opioid수용체는 adenylate cyclase의 활성을 억제하므로써 cyclic AMP의 양을 감소시킨다. 본 연구에서는 striatum에서 dopamine과 opioid 신경전달계의 상호관계를 알아보고자 haloperidol(750ug/kg)을 10일간 복강내 투여하여 dopaminergic pathway를 차단시킨후 mouse striatum에서 선택적 opioid ${\mu},\;{\gamma}\;{\kappa}$ 수용체 agonist들에 의해 축적되는 cAMP양을 측정하여 본 결과, haloperidol단독투여에 의해서 cAMP는 유의한 증가를 나타내었으며, haloperidol 장기투여된 mouse striatum 에서 morphine(20mg/kg), DAGO(5Oug/kg), DPDPE(50ug/kg), U5O,488H (500ug/kg)투여에 의해서 haloperidol에 의한 cAMP 증가는 억제되었으며, 정상 mouse에 투여된 morphine, DAGO, DPDPE, U5O,488H에 비해서는 DAGO, DPDPE 투여군에서 증가를 나타내었다. Haloperidol장기투여로 인한 morphine, DAGO, DPDPE, U5O,488H의 영향은 naloxone에 의해서 morphine과 U5O, 488H투여군에서 길항되었으며 정상 mouse에 투여된 morphine, DAGO, DPDPE, U5O,488H에 의한 cAMP의 감소는 naloxone에 의하여 모든 실험군에서 길항되었다. 이상의 결과로 보아 dopaminergic denervation시 mouse striatum에서 ${\mu},\;{\gamma},\;{\kappa}$효현제에 의하여 축적되는 cAMP양은 ${\kappa}$수용체 효현제인 U5O,488H에서 가장 현저한 감소를 보여 각 수용체의 활성화정도는 변화되며, 그중에서 ${\kappa}$수용체는 그 기능이 가장 보존되고 있음을 알 수 있었다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2004년도 Annual Meeting of the Korean Society ofApplied Pharmacology
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• pp.95-99
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• 2004

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2003년도 학술발표대회 발표논문초록집
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• pp.75-75
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• 2003

Since the establishment of embryonic stem cell, pluripotency of the cells was known to allow differentiation of the cells into various cell types consisting whole body. Several protocols have been developed to induce expression of specific genes.. However, no precise protocol that will generate a single type of the cells from stem cells has been reported. In order to produce cells suitable for transplantion into brain of PD animal model, which arouse due to a progressive degeneration of dopaminergic neurons in midbrain, human embryonic stem cell (hESC, MB03) was transfected with cDNAs cording for tyrosine hydroxylase (TH). Successful transfection was confirmed by western immunoblotting. Newly transfected cell line (TH#2/MB03) was induced to differentiate by the two neurogenic factors retinoic acid (RA) and b-FGF. Exp. I) Upon differentiation using RA/ascorbic acid (AA), embryoid bodies (EB, for 4days) derived from hES cells were exposed to RA (10$^{-6}$ M)/AA (50 mM) for 4 days, and were allowed to differentiate in N2 medium for 7, 14, 21, or 28 days. Exp. II) When bFGF was used, neuronal precursor cells were selected for 8 days in N2 medium after EB formation. After selection, cells were expanded at the presence of bFGF (20 ng/ml) for another 6 days followed by a final differentiation in N2 medium for 7, 14, 21 or 28 days. By indirect immunocytochemical studies, proportion of cells expressing NF200 increased rapidly from 20% at 7 days to 70 % at 28 days in RA/AA-treated group, while those cells expressing NF160 decreased from 80% at 7 days to 10% at 28 days upon differentiation in N2 medium. However, in differentiation by RA/AA treatment system, there was a significant increase in proportion of neuron maturity (73%) at day 14 after N2 medium. TH#2/MB03 cells expressing TH are >90% when matured at the absence of either bDNF or TGF-$\alpha$. These results suggested that TH#2/MB03 cells could be differentiated in vitro into mature neurons by RA/AA.

• Journal of Korean Neurosurgical Society
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• 제38권6호
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• pp.456-464
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• 2005

Objective : The authors investigated whether rotenone induces cellular death also in non-dopaminergic neurons and high concentration of potassium ion can show protective effect for non-dopaminergic neuron in case of rotenone-induced cytotoxicity. Methods : Neuro 2A cells was treated with rotenone, and their survival as well as cell death mechanism was estimated using 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium[MTT] assay, Lactate dehydrogenase[LDH] release assay, fluorescence microscopy, and agarose gel electrophoresis. The changes in rotenone-treated cells was also studied after co-treatment of 50mM KCl. And the protective effect of KCl was evaluated by mitochondrial membrane potential assay and compared with the effects of various antioxidants. Results : Neuro 2A cells treated with rotenone underwent apoptotic death showing chromosome condensation and fragmentation as well as DNA laddering. Co-incubation of neuro 2A cells with 50mM KCl prevented it from the cytotoxicity induced by rotenone. Intracellular accumulation of reactive oxygen species[ROS] resulting by rotenone were significantly reduced by 50mM KCl. Potassium exhibited significantly similar potency compared to the antioxidants. Conclusion : The present findings showed that potassium attenuated rotenone-induced cytotoxicity, intracellular accumulation of ROS, and fragmentation of DNA in Neuro 2A cells. These findings suggest the therapeutic potential of potassium ion in neuronal apoptosis, but the practical application of high concentration of potassium ion remains to be settled.