• 한국동물생명공학회지
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• 제38권2호
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• pp.77-83
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• 2023

Background: Serotonin receptors can be divided into seven different families with various subtypes. The serotonin 1A (5-HT1A) receptor is one of the most abundant subtypes in animal brains. The expression of 5-HT1A receptors in the brain has been reported in various animals but has not been studied in horses. The 5-HT1A receptor functions related to emotions and behaviors, thus it is important to understand the functional effects and distribution of 5-HT1A receptors in horses to better understand horse behavior and its associated mechanism. Methods: Brain samples from seven different regions, which were the frontal, central, and posterior cerebral cortices, cerebellar cortex and medulla, thalamus, and hypothalamus, were collected from six horses. Western blot analysis was performed to validate the cross-reactivity of rabbit anti-5-HT1A receptor antibody in horse samples. Immunofluorescence was performed to evaluate the localization of 5-HT1A receptors in the brains. Results: The protein bands of 5-HT1A receptor appeared at approximately 50 kDa in the frontal, central, and posterior cerebral cortices, cerebellar cortex, thalamus, and hypothalamus. In contrast, no band was observed in the cerebellar medulla. Immunofluorescence analysis showed that the cytoplasm of neurons in the cerebral cortices, thalamus, and hypothalamus were immunostained for 5-HT1A receptors. In the cerebellar cortex, 5-HT1A was localized in the cytoplasm of Purkinje cells. Conclusions: In conclusion, the study suggests that 5-HT and 5-HT1A receptor systems may play important roles in the central nervous system of horses, based on the widespread distribution of the receptors in the horse brain.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제12권2호
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• pp.165-178
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• 2001

주의력결핍 ${\cdot}$ 과잉운동장애(이하 ADHD라 기술함)의 생화학적인 원인을 규명하고 개체발생적인 과정에 대한 이해를 하기 위하여 46명의 ADHD아동들과 18명의 발달성언어장애 아동들을 대상으로 혈장내 의 5-HT와 5-HIAA 함량을 측정하고 개체발생적인 과정에 대한 연구를 시행한 결과 다음과 같은 결과를 얻었다. 1) 대상군과 대조군에서 혈장 5-HT(serotonin) 함량비교에서는 혼합형(combined type)은 평균치 17.81 ng/ml, 주의력결핍형은 22.00ng/ml, 과잉운동 ${\cdot}$ 충동형은 24.75ng/ml 대조군의 평균치는 31.83 ng/ml로서 분산분석 결과 의미있는 차이가 관찰되었으며(F=4.33, df 3, 60, p<0.05), Scheffe씨법을 이용한 사후검증에서는 혼합형과 대조군간에는 의미있는 차이가 관찰되었으나 나머지 군간에는 의미있는 차이가 관찰되지 않았다. 2) 대상군과 대조군에서 혈장 5-HIAA함량 비교에서는 의미있는 차이가 관찰되지 않았다(F=2.08, df 3, 60, p>0.05). 3) ADHD전체군과 대조군간의 5-HT 및 5-HIAA함량비교에서는 5-HT함량의 평균치는 21.74ng/ml 이었으며, 대조군의 평균치는 31.83ng/ml로서 의미있는 차이가 관찰되었다(T=3.10, df 62, p<0.05). 그러나, 5-HIAA함량치는 의미있는 차이가 없었다(T=1.90, df 62, p>0.05). 4) ADHD군에서 TOVA소견과 5-HT 및 5-HIAA 함량간의 상관성에 있어서는 의미있는 상관성이 관찰되지 않았다. 5) ADHD군에서 DSM-IV소견과 5-HT 및 5-HIAA함량간의 상관성에 있어서도 의미있는 상관성은 관찰되지 않았다. 6) 대상군과 대조군에서 혈장 5-HT(serotonin)함량과 연령간의 상관성에 있어서는 모두 의미있는 상관성은 관찰되지 않았다(ADHD군：Pearson 상관계수 -0.20, 대조군：-0.05, 모두 p>0.05). 7) 대상군과 대조군에서 혈장 5-HIAA함량과 연령간의 상관성에 있어서도 모두 의미있는 상관성은 관찰되지 않았다(ADHD군：Pearson 상관계수 -0.17, 대조군：0.04, 모두 p>0.05). 이러한 소견으로 미루어 5-HT의 농도저하가 ADHD의 원인중의 일부로 작용할 가능성이 있으며, 5-HT 의 개체발생적인 측면에 있어서는 이상소견이 없을 가능성이 있다. 향후 생화학적인 소견에 의한 아형으로의 분류가 가능할 것으로 생각되면 이러한 분류에 의하여 약물에 대한 반응, 가족력의 차이 또는 예후에 대한 연구가 시행되어야 한다.

• 대한약리학회지
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• 제2권1호
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• pp.71-82
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• 1966

The inhibitory effect of 5-hydroxytryptamine (5-HT) on the isolated intestinal strips of the tortoise (Amyda japonica), rat, rabbit and guinea pig was investigated. 1) The strips from the middle or lower part of the tortoise intestine responded with relaxation to 5-HT $(10^{-9}{\sim}10^{-5}g/ml)$, and the magnitude of the relaxation was proportional to the dose of 5-HT. The rectal part of the tortoise intestine, in contrast, showed contraction, the magnitude of which also was proportional to the dose of 5-HT. 2) Various blocking agents such as methysergide, morphine, tetracaine, nethalide, bretylium, hexamethonium, mecamylamine and chlorisondamine, showed no selective blocking activity on the relaxant effect of 5-HT on the tortoise intestine. The inhibitory effect of isoproterenol on the tortoise intestine, however, was selectively blocked by nethalide, and the stimulatory effect of 5-HT on the rectal part of the tortoise was blocked by methysergide. 3) In the presence of 5-HT, the stimulatory effect of DMPP on the tortoise intestine was remarkably attenuated, whereas that of acetylcholine and $BaCl_2$ was little affected. In the presence of isoproterenol, the stimulatory effect of acetylcholine and $BaCl_2$ were affected, but that of DMPP was little affected. 4) Large dose of 5-HT($10^{-4}$g/ml) produced inhibitory effect on the strips from the distal part of the isolated colon of the rat, rabbit and guinea pig, when the strips had been exposed to 5-HT($10^{-4}$g/ml), methysergide or phen`oxybenzamine. 5) Bretylium, as well as nethalide, abolished or remarkably reduced, in a few cases of the experiments, the inhibitory effect of the large dose of 5-HT on the distal part of the colon, whereas morphine did not affect it. 6) The ileal strips of the guinea pig also showed relaxation, as in the colonic strips, having been exposed to the large dose of 5-HT or phenoxybenzamine. This effect, however, was not obsered in the case of the rabbit ileum. 7) The property of the action-site of 5-HT in the tortoise intestine seemd to be different from the 5-HT receptors which have been revealed by several investigators. 8) Adrenergic component seemed to be participated in the inhibitory effect of 5-HT on the colon of the rat and rabbit.

• The Korean Journal of Physiology and Pharmacology
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• 제11권5호
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• pp.221-226
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• 2007

Melittin-induced tonic pain model is characterized by local inflammation, edema, spontaneous flinchings, and sustained mechanical hypersensitivity. These nociceptive responses are mediated through selective activation of capsaicin-sensitive primary afferent fibers by melittin. The present study was undertaken to elucidate the role of peripheral 5-hydroxytryptamine(5-HT) receptors in the melittin-induced nociceptive responses. Changes in mechanical threshold, flinching behaviors and paw thickness were measured in rat intraplantarly injected with melittin($40{\mu}g/paw$) alone or treated together with melittin and 5-HT receptor antagonists. WAY-100635($100{\mu}g\;&\;200{\mu}g/paw$), isamoltane hemifumarate($100{\mu}g\;&\;200{\mu}g/paw$), methysergide maleate($60{\mu}g,\;120{\mu}g\;&\;200{\mu}g/paw$) and ICS-205,930($100{\mu}g\;&\;200{\mu}g/paw$) were intraplantarly injected 20 min before melittin injection. All 5-HT receptor antagonists tested in this experiment significantly attenuated the ability of melittin to reduce mechanical threshold and to induce flinching behaviors. 5-HT receptor antagonists, except ICS-205,930, had mild inhibitory effect on melittin-induced edema. These experimental findings suggest that multiple peripheral 5-HT receptors are involved in the melittin-induced nociceptive responses.

• Toxicological Research
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• 제12권2호
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• pp.171-179
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• 1996

To investigate the involvement of $5-HT_{2A}/ 5-HT_{2C} receptors in the developmental toxicity of cocaine in rats, mianserin (2.5 mg/kg), a $5-HT_{2A}/5-HT_{2C}$ receptor antagonist, and/or cocaine HCl (45 mg/kg) were administered intraperitoneally (i.p.), during postnatal days (PND) 7-13. Behavioral assessments for the rat pups were done after 100 days of age by using the progressive ratio schedule of reinforcement (FR 1-FR 128, doubled everyday) and cocaine challenge (5, 15 or 30 mg/kg i.p.) upon established FR 32 behavior. Cocaine injected just prior to the FR 32 session suppressed the established FR 32 responding in a dose-dependent manner. The low dose of cocaine did not affect the FR 32 responding, while the high dose of cocaine suppressed it in all experimental groups. However, by the middle dose of cocaine, rats previously received water-cocaine in their early life showed a marked resistance to cocaine-induced behavioral suppression, and this resistance was not observed in rats received both mianserin and cocaine in their early life. These results suggest that $5-HT_{2A}/ 5-HT_{2C}$ receptors may have an important role for the persistently altered behavioral sensitivity to cocaine caused by exposure to cocaine during development.

• The Korean Journal of Physiology and Pharmacology
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• 제15권3호
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• pp.129-135
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• 2011

In this study we determined whether or not 5-hydroxytryptamine (5-HT) has an effect on the pacemaker activities of interstitial cells of Cajal (ICC) from the mouse small intestine. The actions of 5-HT on pacemaker activities were investigated using a whole-cell patch-clamp technique, intracellular $Ca^{2+}$ ($[Ca^{2+}]_i$) analysis, and RT-PCR in ICC. Exogenously-treated 5-HT showed tonic inward currents on pacemaker currents in ICC under the voltage-clamp mode in a dose-dependent manner. Based on RT-PCR results, we found the existence of 5-$HT_{2B,\;3,\;4,\;and\;7}$ receptors in ICC. However, SDZ 205557 (a 5-$HT_4$ receptor antagonist), SB 269970 (a 5-$HT_7$ receptor antagonist), 3-tropanylindole - 3 - carboxylate methiodide (3-TCM; a 5-$HT_3$ antagonist) blocked the 5-HT-induced action on pacemaker activity, but not SB 204741 (a 5-$HT_{2B}$ receptor antagonist). Based on $[Ca^{2+}]_i$ analysis, we found that 5-HT increased the intensity of $[Ca^{2+}]_i$. The treatment of PD 98059 or JNK II inhibitor blocked the 5-HT-induced action on pacemaker activity of ICC, but not SB 203580. In summary, these results suggest that 5-HT can modulate pacemaker activity through 5-$HT_{3,\;4,\;and\;7}$ receptors via $[Ca^{2+}]_i$ mobilization and regulation of mitogen-activated protein kinases.

• 생물정신의학
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• 제5권2호
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• pp.215-218
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• 1998

The $5-HT_{2A}$ receptor is of great interest for research into schizophrenia and psychopharmacology in light of the observation that schizophrenic patients has 5-HT cortical-subcortical imbalance and atypical antipsychotic clozpine has $5-HT_{2A}$ antagonists properties. An significant association between schizophrenia and the T102C polymorphism of the gene for $5-HT_{2A}$receptor has been reported. In this study, we investigated an association between schizophrenia and the T102C polymorphism of the gene for $5-HT_{2A}$ receptor in Korean schizophrenic patients. The subjects consisted of 139 schizophrenic patients and 88 normal controls. Genomic DNA was amplified by PCR and digested with MsPI. The uncutt product identified allele 1(nucleotide sequence TCT) ; digested products of 216bp and 156bp identified allele 2(nucleotide sequence TCC). The allele frequencies and the genotypic distribution of $5-HT_{2A}$ receptor gene were not significantly different between schizophrenic patients and normal controls. Since allele frequencies of the T102C polymorphism may differ between individuals of different ethnic backgrounds, it needs to be conducted in an advanced research.

• BMB Reports
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• 제51권4호
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• pp.188-193
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• 2018

Caffeoylserotonin (CaS), one derivative of serotonin (5-HT), is a secondary metabolite produced in pepper fruits with strong antioxidant activities. In this study, we investigated the effect of CaS on proliferation and migration of human keratinocyte HaCaT cells compared to that of 5-HT. CaS enhanced keratinocyte proliferation even under serum deficient condition. This effect of CaS was mediated by serotonin 2B receptor (5-HT2BR) related to the cell proliferation effect of 5-HT. We also confirmed that both CaS and 5-HT induced G1 progression via 5-HT2BR/ERK pathway in HaCaT cells. However, Akt pathway was additionally involved in upregulated expression levels of cyclin D1 and cyclin E induced by CaS by activating 5-HT2BR. Moreover, CaS and 5-HT induced cell migration in HaCaT cells via 5-HT2BR. However, 5-HT regulated cell migration only through ERK/AP-1/MMP9 pathway while additional Akt/NF-${\kappa}B$/MMP9 pathway was involved in the cell migration effect of CaS. These results suggest that CaS can enhance keratinocyte proliferation and migration. It might have potential as a reagent beneficial for wound closing and cell regeneration.

• The Korean Journal of Physiology and Pharmacology
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• 제7권6호
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• pp.295-301
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• 2003

Striatum plays a crucial role in the movement control and habitual learning. It receives an information from wide area of cerebral cortex as well as an extensive serotonergic (5-hydroxytryptamine, 5-HT) input from raphe nuclei. In the present study, the effects of 5-HT to modulate synaptic transmission were studied in the rat corticostriatal brain slice using in vitro extracellular recording technique. Synaptic responses were evoked by stimulation of cortical glutamatergic inputs on the corpus callosum and recorded in the dorsal striatum. 5-HT reversibly inhibited coticostriatal glutamatergic synaptic transmission in a dose-dependent fashion (5, 10, 50, and $10{\mu}M$), maximally reducing in the corticostriatal population spike (PS) amplitude to $40.1{\pm}5.0$% at a concentration of $50{\mu}M$ 5-HT. PSs mediated by non-NMDA glutamate receptors, which were isolated by bath application of the NMDA receptor antagonist, d,l-2-amino-5-phospohonovaleric acid (AP-V), were decreased by application of $50{\mu}M$ 5-HT. However, PSs mediated by NMDA receptors, that were activated by application of zero $Mg^{2+}$ aCSF, were not significantly affected by $50{\mu}M$ 5-HT. To test whether the corticostriatal synaptic inhibitions by 5-HT might involve a change in the probability of neurotransmitter release from presynaptic nerve terminals, we measured the paired-pulse ratio (PPR) evoked by 2 identical pulses (50 ms interpulse interval), and found that PPR was increased ($33.4{\pm}5.2$%) by 5-HT, reflecting decreased neurotransmitter releasing probability. These results suggest that 5-HT may decrease neurotransmitter release probability of glutamatergic corticostriatal synapse and may be able to selectively decrease non-NMDA glutamate receptor-mediated synaptic transmission.

• Transactions on Electrical and Electronic Materials
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• 제13권5호
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• pp.237-240
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• 2012

A conducting polymer, poly 3-hexylthiophene (P3HT) is characterized with the metal-insulator-semiconductor (MIS) measurement method and the high frequency planar circuit method. From the MIS measurement method, the relative dielectric constant of the P3HT film is estimated to be 4.4. For the high frequency planar circuit method, a coplanar waveguide is fabricated on the P3HT film. When applying +20 V to the CPW on P3HT film, the P3HT film is in accumulation mode and becomes lossy. The CPW on P3HT film is 1.5 dB lossier than the CPW on $SiO_2$ film without P3HT film at 50 GHz.