• Toxicological Research
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• v.13 no.4
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• pp.359-365
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• 1997

Many factors are known to be responsible for cerebral ischemic injury, such as excitatory neurotransmitters, increased intraneuronal calcium, or disturbance of cellular energy metabolism. Recently, oxygen free radicals, formed during ischemia/reperfusion, have been proposed as one of the main causes of ischemia/reperfusion injury. Therefore, to investigate the role of oxygen free radical during ischemia/reperfusion, in the present study the effect of endogenous oxygen free radical scavenger, superoxide dismutase / catalase(SOD / catalase) on the release of [$^3$H]-5-hydroxytryptamine([$^3$H]-5-HT) during hypoxia/reoxygenation in rat hippocampal slices was measured. The hippocampus was obtained from the rat brain and sliced 400 gm thickness with manual chopper. After 30 min's preincubation in the normal buffer, the slices were incubated for 20 min in a buffer containing [$^3$H]-5-HT(0.1 $\mu$M, 74 $\mu$Ci) for uptake, and washed. To measure the release of [$^3$H]-5-HT into the buffer, the incubation medium was drained off and refilled every ten minutes through a sequence of 14 tubes. Induction of hypoxia for 20 min (gassing it with 95% N$_2$/5% CO$_2$) was done in the 6th and 7th tube, and oxygen free radical scavenger, SOD / catalase was added 10 minutes prior to induction of hypoxia. The radioactivity in each buffer and the tissue were counted using liquid scintillation counter and the results were expressed as a percentage of the total activity. When slices were exposed to hypoxia for 20 min, [$^3$H]-5-HT release was markedly decreased and a rebound release of [$^3$H]-5-HT was observed on the post-hypoxic reoxygenation period. SOD / catalase did not changed the release of [$^3$H]-5-HT in control group, but inhibited the decrease of [$^3$H]-5-HT release in hypoxic period and rebound increase of [$^3$H]-5-HT in reoxygenation period. This result suggest that superoxide anion may play a role in the hypoxic-, and reoxygenation-induced change of [$^3$H]-5-HT release in rat hippocampal slices.

• Development and Reproduction
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• v.13 no.4
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• pp.341-351
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• 2009

The effects of serotonin (5-hydroxytryptamine, 5-HT), ecdysone (20-hydroxyecdysone, 20-E) and HCG (human chorionic gonadotropin) on the ovarian maturation of the fleshy shrimp, Fenneropenaeus chinensis were investigated. Adult female fleshy shrimps were injected with 5-HT ($5{\mu}g$/g body weight (BW) or $20{\mu}g$/g BW), 20-E ($5{\mu}g$/g BW, $10{\mu}g$/g BW or $20{\mu}g$/g BW) or HCG (5 IU/g BW or 10 IU/g BW) three times at 5-day intervals and were sacrificed 10 days after the last injection. The effects were compared against an intact control group and sham control group which received the injection of sterile saline solution as a vehicle. 20-E and HCG showed no effectiveness on ovarian maturation in fleshy shrimps. However flesh shrimp given 5-HT of $20{\mu}g$/g BW showed significant increase in gonadosomatic index (GSI) in early spring. The results suggest that treatment of 5-HT of $20{\mu}g$/g BW or more is useful approach for the nursery production of the fleshy shrimp, Fenneropenaeus chinensis aquaculture.

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.5
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• pp.255-262
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• 2005

Striatum is involved in the control of movement and habitual memory. It receives glutamatergic input from wide area of the cerebral cortex as well as an extensive serotonergic (5-hydroxytryptamine, 5-HT) input from the raphe nuclei. In our study, the effects of 5-HT on synaptic transmission were studied in the rat corticostriatal brain slice using in vitro whole-cell recording technique. 5-HT inhibited the amplitude as well as frequency of spontaneous excitatory postsynaptic currents (sEPSC) significantly, and neither ${\gamma}-aminobutyric$ acid (GABA)A receptor antagonist bicuculline (BIC), nor $N-methyl-_{D}-aspartate$ (NMDA) receptor antagonist, $_{DL}-2-amino-5-phosphonovaleric$ acid (AP-V) could block the effect of 5-HT. In the presence non-NMDA receptor antagonist, 2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenxo[f] quinoxaline-7-sulfonamide (NBQX), the inhibitory effect of 5-HT was blocked. We also figured out that 5-HT change the channel kinetics of the sEPSC. There was a significant increase in the rise time during the 5-HT application. Our results suggest that 5-HT has an effect on both pre- and postsynaptic site with decreasing neurotransmitter release probability of glutamate and decreasing the sensitivity to glutamate by increasing the rise time of non-NMDA receptor mediated synaptic transmission in the corticostriatal synapses.

• The Journal of Korean Physical Therapy
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• v.16 no.3
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• pp.22-31
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• 2004

The purpose of this study was to demonstrate the effects of silver spike point (SSP) low frequency electrical stimulation on plasma ${\beta}-endorphin$ activities measured by radio- immunoassay from normal volunteer and the effects of ${\beta}-endorphin$ on 5-hydroxytryptamine (5-HT, serotonin)-induced contraction investigated by isometric tension methode in rats. The current of 3 Hz continue type, but not 100 Hz continue type, of SSP low frequency electrical stimulation significantly increased in plasma ${\beta}-endorphin$ from normal volunteer. The endothelial cell-dependent 5-HT-induced contractions were inhibited by ${\beta}-endorphin$ $1{\mu}M$. These results suggest that the ${\beta}-endorphin$ regulates nociceptive-like substance, such as 5-HT, in part and that the SSP low frequency electrical stimulation, specifically current of low frequency of 3 Hz continue type, significantly increases plasma ${\beta}-endorphin$ from normal volunteer.

• The Korean Journal of Pharmacology
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• v.20 no.2
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• pp.73-80
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• 1984

The effect of higenamine and its derivatives on the activity of rat bran mitochondrial monoamine oxidase(MAO) was studied. Methoxyhigenamine of drugs tested had no effect on isometric contraction of heart and reversibly inhibited MAO towards 5-hydroxytryptamine(5-HT) and phenylethylamine(PEA) in a pure competitive fashion and in a hyperbolic mixed fashion, respectively, but was found to be relatively MAO-A selective inhibitor, with IC50 value for 5-HT lower ten fold than for PEA. The results suggest that methoxyhigenamine is a reversible, relatively MAO-A specific inhibitor in virto.

• Korean Journal of Pharmacognosy
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• v.26 no.4
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• pp.349-354
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• 1995

Crude methanolic(80%) extracts from 109 kinds of traditional herbal drugs were randomly screened for inhibitory effects on 5-hydroxytryptamine(5-HT) uptake in primary cultured rat brainstem neurons. Rat brainstem neurons were cultured from embryonic day 14, and maintained for 7-9 days in vitro. Clomipramine (500 nM), a reference drug, decreased 5-HT uptake to 16% of control values. Of the 109 herbal drugs screened, Citri immaturi Pericarpium(靑皮), Coptidis Rhizoma(黃蓮), Cnidii Rhizoma(土川芎) showed the most potent 5-HT uptake inhibiting activities. These herbal drugs, at the concentration of $10{\;}{\mu}g/ml$, inhibited 5-HT uptake 69, 69, and 57% respectively, when inhibition(%) was expressed as a relative value compared to the 500 nM clomipramine-induced inhibition.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1992.05a
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• pp.39-39
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• 1992

5-Hydroxytryptamine(serotonin, 5-HT)은 중추신경의 신경 전달물질로서 조울병, 불안신경증 등의 정신병태생리에 중요한 역할을 한다. Radioligand 결합실험에 의하여 5-$HT_{1A}$, 5-$HT_{1B}$, 5-$HT_{1C}$, 5-$HT_{1D}$, 5-$HT_{2}$, 5-$HT_3$의 5-HT receptor subtypes의 존재가 확인되어 있고, 그 중에서도 5-$HT_{1A}$ receptor는 중추작용 증 정 도의 조절에 관계가 깊은 raphe nuclei 및 해마에 주로 존재하여 약리학적으로는 체온강하, 혈압 강하, 과식작용, corticosterone 분비 등과 관련되어 있음이 알려져 있다. 따라서 본 수용체 agonist가 항불안약, 항우울약 또는 항고혈압약으로서의 응용이 가능해지면서 5-$HT_{1A}$ 수용체 기능의 해명 및 그 agonist의 개발이 주목받고 있는 가운데, 본 연구에 있어서, 항불안약 개발목적으로 합성된 일련의 화합물 중 1-<3-(3,4-methylene-dioxyphenoxy)propyl> 4-phenyl piperazine (DP-554)이 5-HT 수용체에 특이적이고 선택적으로 높은 친화성을 가지며, rat 해마의 막분획에서 adenylate cyclase 활성을 억제하고, 뇌내 5-HT turnover rate를 감소시키는 둥의 약리학적 작용을 나타내어, 이 화합물이 5-$HT_{1A}$ receptor agonist로서 작용함을 밝혔다. Mouse vas deferens (MVD)를 이용한 실험에서 5-$HT_{1A}$ receptor가 MVD의 교감신경 말단에 존재하여 그 neurotransmission을 억제함이 시사되었으며, 이 조직에서 또한 5-$HT_2$와 5-$HT_3$ 수용체의 존재를 확인하고 각각의 기능을 분명히 했다.

• The Korean Journal of Pharmacology
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• v.26 no.2
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• pp.153-160
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• 1990

5-Hydroxytryptamine (5-HT) was reported to elicit natriuresis and diuresis when given intracerebroventricularly (icv) and these effects were shown to be abolished by icv methysergide, $5-HT{_1}$ antagonist, thus suggesting that central tryptaminergic system may also participate in the regulation of renal function. We tried in this study to elucidate the role of $5-HT_2$ receptors in the central tryptaminergic regulation of renal function, observing the effects of icv ketanserin, a specific $5-HT_2$ antagonist. Ketanserin (KET) icv in doses of $120{\mu}g$ $(=0.3\;{\mu}moles)/kg$ produced significant natriuresis without affecting renal hemodynamics, indicating that it resulted from decreased tubular Na reabsorption. Systemic blood pressure decreased slightly but significantly. When given iv, no significant effect was observed. 5-HT, $200{\mu}g/kg$ icv, produced mild but significant natriuresis and diuresis. However, after KET, $40{\mu}\;g/kg$ icv, a dose which minimally affects renal function, the natriuresis and diuresis by 5-HT was greatly augmented, with the fractional excretion of filtered sodium reaching 9.3%. The renal effects of other biogenic amines administered icv, such as norepinephrine, dopamine and histamine, were not significantly affected by the KET pretreatment. These observations suggest that central tryptaminergic system influences renal function in dual ways, i.e., natriuretic and diuretic influence via $5-HT_1$ receptors, whereas $5-HT_2$ subtypes mediate the antinatriuretic and antidiuretic effects, and that the central tryptaminergic system plays a role in the regulation of rabbit renal function.

• Journal of Animal Science and Technology
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• v.64 no.5
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• pp.922-936
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• 2022

5-Hydroxytryptamine (5-HT), a monoamine, as a local regulator in the mammary gland is a chemical signal produced by the mammary epithelium cell. In cows, studies have shown that 5-HT is associated with epithelial cell apoptosis during the degenerative phase of the mammary gland. However, studies in other tissues have shown that 5-HT can effectively promote cell viability. Whether 5-HT could have an effect on mammary cell viability in dairy cows is still unknown. The purpose of this study was to determine: (1) effect of 5-HT on the viability of bovine mammary epithelial cells and its related signaling pathways, (2) interaction between prolactin (PRL) and 5-HT on the cell viability. The bovine mammary alveolar cell-T (MAC-T) were cultured with different concentrations of 5-HT for 12, 24, 48 or 72 hours, and then were assayed using cell counting kit-8, polymerase chain reaction (PCR) and immunobloting. The results suggested that 20 μM 5-HT treatment for 12 or 24 h promote cell viability, which was mainly induced by the activation of 5-HT receptor (5-HTR) 1B and 4, because the increase caused by 5-HT vanished when 5-HTR 1B and 4 was blocked by SB224289 and SB204070. And protein expression of mammalian target of rapamycin (mTOR), eukaryotic translation elongation factor 2 (eEF2), janus kinase 2 (JAK2) and signal transducer and activator of transcription 5 (STAT5) were decreased after blocking 5-HT 1B and 4 receptors. When MAC-T cells were treated with 5-HT and PRL simultaneously for 24 h, both the cell viability and the level of mTOR protein were significantly higher than that cultured with 5-HT or PRL alone. In conclusion, our study suggested that 5-HT promotes the viability of MAC-T cells by 5-HTR 1B and/or 4. Furthermore, there is a reciprocal relationship between PRL and 5-HT.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.282-282
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• 1994

Radioligand결합실험에 의하여 7가지 이상의 5-hydroxytryptamine serotonin, 5-HT)수용체 subtype가 규명되어 있고, 1983년 5-HT agonist로 알려져 있던 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT)가 〔$^3$H〕5-HT수용체에 대한 결합만을 선택적으로 억제하며, 본 수용체를 직접 표식함이 알려진 이래, 본 수용체의 기능에 대한 연구가 계속되어 오고있다. 특히 항불안약으로 임상에 사용되어 왔던 benzodiazepines이 5-HT neuron의 활성을 억제한다는 사실이 보고되면서 5-HT neuron과 불안과의 관련에 관한 연구가 계속되고 있는 가운데, 새로운 항불안약으로 주목을 받고 있던 buspirone이 5-$HT_{1A}$ 수용체에 높은 친화성을 가짐이 확인되었다. 그 외에도 5-$HT_{1A}$ 수용체작용약이 항우울약, 항고혈압약으로서의 응용가능성 이 시사되면서 본 수용체작용약의 개발 및 그 기능해명이 주목을 받고 있다. 본 연구에서는, 5-$HT_{1A}$ 수용체작용약인 8-OH-DPAT와 항불안약을 개발할 목적으로 합성된 화합물인 1-[3-(3,4-methylenedioxyphenoxy)propy〕-4-phenyl piperazine (8P-554)을 이용하여, 화합물의 5-HT$_{1A}$수용체에 대한 친화성을 검토하는 방법과. 본 수용체를 통하여 나타난다고 알려져 있는 5-HT의 약리작용을 검토하는 방법을 기술하므로서, 여러가지 임상적 응용을 위하여 새롭게 합성되는 화합물의 5-$HT_{1A}$ 수용체와의 상호작용을 검색하는 방법을 제시하고자 한다.다.