• Journal of Ginseng Research
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• v.21 no.1
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• pp.61-67
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• 1997

The present study examined the characteristics of behavior Induced by dopamine agonists following treatment with 6-hydroxydopamine(6-OHDA) unilaterally into left striatum in rats. 6-OHDA was administered at doses of 8,16 and 24 $\mu\textrm{g}$/$\mu\textrm{l}$(in 0.1% ascorbic acid) into dopaminergic neurons in left striatum of 7 weeks old rat under anesthetic. Locomotor activity was significantly decreased at 1 week following 6-OHDA-administration in 7 weeks old rats. The contralateral circling behavior was induced by apomorphine(5 mg/kg, i.v.) after 1 week following 6-OHDA(24$\mu\textrm{g}$/$\mu\textrm{l}$) treatment, and was further increased by repeated administration of apomorphine at 2, 3 and 4 weeks. The contralateral circling behavior was also induced by lisuride and 1-dopa in a dose dependent manner, but not by SK & F 82526 in 7 weeks old rats treated with 6-OHDA. The contralateral circling behavior was significantly higher in 21 weeks old rats but significantly lower In 35 weeks old rats when compared with 7 weeks old rats. The contralateral circling behavior induced by apomorphlne did not differ significantly in 7 and 35 weeks old male and female rats. These results suggest that 6-OHDA treatment into left striatum causes remarkable destrurtion of intrastriatal dopaminergic netcons leading to dopaminergic receptor supersensitivity. Thus, the contralateral circling behavior in duces by apomorphine may be used as indicator for neurodegenerative diseases.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.4
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• pp.980-990
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• 2003

The effect of Gamigyuibi-tang on the penile erection induced by apomorphine HCI and on the erectile dysfunction induced by p,p-DDE, an environmental hormone derivate of DOT, were monitored using male cats. The changes of penile length, diameter, erectic periods and histological profiles of corpus cavernosum and corpus spongiosum were observed with blood testosterone levels. In conclusion, dose-dependent and significant increase of penile length, diameter, erectic periods and blood testosterone levels were detected in the Gamigyuibitang-dosing groups compared to other groups. In addition, it is also demonstrated that the increasement of congestion of blood vessels and dilation of connective tissues, and decreasement of adipocytes in the corpus cavernosum and/or corpus spongiosum of the Gamigyuibitang-dosing groups. According to these results, it is considered that Gamigyuibitang has some augmentation effect against to apomorphine HCI inducing penile erection and it also suggested that Gamigyuibitang has favorable effect to treatment of erectic dysfunctions induced by p,p-DDE.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.247-247
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• 1996

Previous work in our laboratory has shown that noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonists, MK-801, ketamine, dextrorphan and dextromethorphan cause a pronounced inhibition of apomorphine-induced cage climbing behavior in intact mice, suggesting the involvement of NMDA receptors in the glutamatergic modulation of dopaminergic function at the postsynaptic dopamine (DA) receptors: Therefore, in order to definitively establish the involvement of NMDA receptor in the apomorphine-induced dopaminergic response at the postsynaptic DA receptor, it is necessary to investigate whether or not the noncompetitive NMDA receptor antagonists would inhibit these phenomena not only in intact mice but also in the mice that are devoid of any involvement of indirect dopaminergic function. To minimize the risk of any indirect involvement of NMDA antagonists with DA neurons, vesicular DA stores were first depleted with reserpine.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.283-283
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• 1994

뇌기능개선 약물들(nootropic drugs)은 항치매약물로 기대되나 현재까지 약리학적으로 공통점이 보고되어 있지는 않다. 최근 수종의 뇌기능 개선약물의 작용이 중추도파민신경 활성을 매개로 함이 보고된바 있다. 따라서 apomorphine 투여에 의해 유발되는 상동행동을 지표로 하여 현재 사용중인 뇌기능개선약물과 국내 자원생약 성분의 작용을 비교 검토하였다. 1. apomorphine 투여에 의하여 유발된 상동행동에 대하여 centrophenoxine 과 N-methyl -D-glucamine은 현저한 상승효과를 나타내었으나 Piracetam은 영향을 미치지 않았다. 2. 인삼사포닌 성분 중 panaxatriol 및 Rgl 성분은 현저한 상승효과를 나타내었으나 total saponine, panaxadiol 및 Rbl 성분은 거의 영향을 미치지 않았다.

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.191.2-192
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• 2001

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.214-214
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• 1996

Intraperitoneal injection of morphine (5 mg/kg) in mice every other day for 8 days produced conditioned place preference (CPP). CPP effects were evaluated by assessing the difference in time spent in the drug-paired compartment and the saline-paired compartment of the place conditioning apparatus. The injection of a non-competitive NMDA antagonist, MK-801 (0.05 and 0.1 mg/kg, i.p.), prior to and during morphine treatment in mice Inhibited morphine-induced CPP. The development of postsynaptic dopamine (DA) receptor supersensitivity in mice displaying a morphine-induced CPP was evidenced by the enhanced response in ambulatory activity to the DA agonist, apomorphine (2 mg/kg). MK-801 inhibited that development of postsynaptic DA receptor supersensitivity MK-801 also inhibited apomorphine-induced climbing behavior, suggesting that MK-801 Inhibits dopaminergic activation mediated via the NMDA receptor.

• Archives of Pharmacal Research
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• v.17 no.3
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• pp.204-206
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• 1994

A regioselective perparation of 10-methoxy-11-hydroxyaporphine ("Apocodeine, 1b") form (R, S)-10, 11-dihydroxyaporphine(apomorphine, 1a) is described. The isopropylidene ketal ring of 10, 11-(isopropylidenyldioxy) aporphine (2) obtained by the isopropylidenation of apomorphine, was regioselectively opened by the ten equivalent of timethylaluminum to give 100-hydroxy-11-t-butyloxyaporphine (3). The free 10-hydroxyl position of 3 was methylated with methyl p-toluenesulfonate/NaH, and afforded 10-methoxy-11-t-butyloxyaporphine (4) in high yield. Selective debutylation gave the desired 10-methoxy-11-hydroxyaporphine("apocodeine", 1b) in good yield.

• Biomolecules & Therapeutics
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• v.14 no.3
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• pp.125-131
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• 2006

The inhibitory effects of (-)-epigallocatechin gallate (EGCG), a major compound of green tea, on the development of locomotor sensitization, conditioned place preference (CPP) and dopamine receptor supersensitivity induced by the repeated administration of morphine were investigated in mice. A single administration of morphine produces hyperlocomotion. The repeated administration of morphine develops sensitization, a progressive enhancement of locomotion, which is used as a model for studying the craving and drug-seeking behaviors characterizing addiction, and CPP, which is used as a model for studying drug reinforcement, respectively. EGCG inhibited morphine-induced hyperlocomotion, sensitization and CPP. In addition, EGCG inhibited the development of postsynaptic dopamine receptors supersensitivity, which may be an underlying common mechanism that mediates the morphine-induced dopaminergic behaviors such as sensitization and CPP. Apomorphine (a dopamine agonist)-induced climbing behaviors also were inhibited by a single direct administration of EGCG These results provide evidence that EGCG has anti-dopaminergic activity, as inhibiting the development of dopamine receptor supersensitivity and apomorphine-induced climbing behaviors. Therefore, it is suggested that green tea may be useful for the prevention and therapy of these adverse actions of morphine.

• Korean Journal of Veterinary Research
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• v.32 no.2
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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.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.6
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• pp.309-315
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• 2006

The protective effects of baicalein, one of the flavonoids in Scutellaria baicalensis Georgi, were evaluated against 6-hydroxydopamine (6-OHDA)-induced neuronal damage in mice and cultured human neuroblastoma cells. Nigrostriatal damage was induced by stereotaxically injecting 6-OHDA into the right striatum. Baicalein was administered intraperitoneally 30 min before and 90 min after lesion induction. Animals received a further daily injection of baicalein for 3 consecutive days. Two weeks after 6-OHDA injection, contralateral rotational asymmetry was observed by apomorphine challenge in lesioned mice. Tyrosine hydroxylase (TH) immunohistochemistry revealed a significant loss of terminals in lesioned striatum and the reduction of the numbers of TH-positive cell in the ipsilateral substantia nigra (SN). In addition, the levels of dopamine (DA) and DA metabolites were reduced and lipid peroxidation was increased in lesioned striatum. However, baicalein treatment reduced apomorphine-induced rotational behavior in 6-OHDA-lesioned mice, and increased TH immunoreactivity in the striatum and SN, and DA levels in lesioned striatum. Lipid peroxidation induced by 6-OHDA was also inhibited by baicalein treatment. Furthermore, when SH-SY5Y human neuroblastoma cells were treated with baicalein, 6-OHDA-induced cytotoxicity and reactive oxygen species (ROS) production were significantly reduced. These results indicate that baicalein effectively protects 6-OHDA-induced neuronal damage through antioxidant action.