• Archives of Pharmacal Research
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• 제22권1호
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• pp.48-54
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• 1999

These studies were designed to examine the differential effect of nitric oxide (NO) and cGMP on glutamate neurotransmission. In primary cultures of rat cerebellar granule cells, the glutamate receptor agonist N-methyl-D-aspartate (NMDA) stimulates the elevation of intracellular calcium concentration ($[Ca^{2+}]_i$), the release of glutamate, the synthesis of NO and an increase of cGMP. Although NO has been shown to stimulate guanylyl cyclase, it is unclear yet whether NO alters the NMDA-induced glutamate release and ${[Ca^{2+}]}_i$ elevation. We showed that the NO synthase inhibitor, NG-monomethyl-L-arginine (NMMA), partially prevented the NMDA-induced release of glutamate and elevation of ${[Ca^{2+}]}_i$ and completely blocked the elevation of cGMP. These effects of NO on glutamate release and [Ca2+]i elevation were unlikely to be secondary to cGMP as the cGMP analogue, dibutyryl cGMP (dBcGMP), did not suppress the effects of NMDA. Rather, dBcGMP slightly augmented the NMDA-induced elevation of ${[Ca^{2+}]}_i$ with no change in the basal level of glutamate or ${[Ca^{2+}]}_i$. The extracellular NO scavenger hydroxocobalamine prevented the NMDA-induced release of glutamate providing indirect evidence that the effect of NO may act on the NMDA receptor. These results suggest that low concentration of NO has a role in maintaining the NMDA receptor activation in a cGMP-independent manner.

• 한국발생생물학회지:발생과생식
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• 제25권3호
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• pp.133-143
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• 2021

In contrast to the human lutropin receptor (hLHR) and rat LHR (rLHR), very few naturally occurring mutants in other mammalian species have been identified. The present study aimed to delineate the mechanism of signal transduction by three constitutively activating mutants (designated M410T, L469R, and D590Y) and two inactivating mutants (D383N and Y546F) of the eel LHR, known to be naturally occurring in human LHR transmembrane domains. The mutants were constructed and measured cyclic adenosine monophosphate (cAMP) accumulation via homogeneous time-resolved fluorescence assays in Chinese hamster ovary (CHO)-K1 cells. The activating mutant cells expressing eel LHR-M410T, L469R, and D590Y exhibited a 4.0-, 19.1-, and 7.8-fold increase in basal cAMP response without agonist treatment, respectively. However, inactivating mutant cells expressing D417N and Y558F did not completely impaired signal transduction. Specifically, signal transduction in the cells expressing activating mutant L469R was not occurred with a further ligand stimulation, showing that the maximal response exhibited approximately 53% of those of wild type receptor. Our results suggested that the constitutively activating mutants of the eel LHR consistently occurred without agonist treatment. These results provide important information of LHR function in fish and regulation with regard to mutations of highly conserved amino acids in glycoprotein hormone receptors.

• Biomolecules & Therapeutics
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• 제30권2호
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• pp.191-202
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• 2022

Tetrazoles were designed and synthesized as potential inhibitors of triple monoamine neurotransmitters (dopamine, norepinephrine, serotonin) reuptake based on the functional and docking simulation of compound 6 which were performed in a previous study. The compound structure consisted of a tetrazole-linker (n)-piperidine/piperazine-spacer (m)-phenyl ring, with tetrazole attached to two phenyl rings (R1 and R2). Altering the carbon number in the linker (n) from 3 to 4 and in the spacer (m) from 0 to 1 increased the potency of serotonin reuptake inhibition. Depending on the nature of piperidine/piperazine, the substituents at R1 and R2 exerted various effects in determining their inhibitory effects on monoamine reuptake. Docking study showed that the selectivity of tetrazole for different transporters was determined based on multiple interactions with various residues on transporters, including hydrophobic residues on transmembrane domains 1, 3, 6, and 8. Co-expression of dopamine transporter, which lowers dopamine concentration in the biophase by uptaking dopamine into the cells, inhibited the dopamine-induced endoctytosis of dopamine D₂ receptor. When tested for compound 40 and 56, compound 40 which has more potent inhibitory activity on dopamine reuptake more strongly disinhibited the inhibitory activity of dopamine transporter on the endocytosis of dopamine D₂ receptor. Overall, we identified candidate inhibitors of triple monoamine neurotransmitter reuptake and provided a theoretical background for identifying such neurotransmitter modifiers for developing novel therapeutic agents of various neuropsychiatric disorders.

• 통합자연과학논문집
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• 제10권3호
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• pp.141-147
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• 2017

Vascular endothelial growth factor (VEGF) is an important signaling protein involved in angiogenesis, which is the formation of new blood vessels from pre-existing vessels. Consequently, blocking of the vascular endothelial growth factor receptor (VEGFR-2) by small molecule inhibitors leads to the inhibition of cancer induced angiogenesis. In this study, we performed a two dimensional quantitative structure activity relationship (2D-QSAR) study of 38 N-Phenyl-N'-{4-(4-quinolyloxy) phenyl} urea derivatives as VEGFR-2 inhibitors based on hologram quantitative structure-activity (HQSAR). The model developed showed reasonable $q^2=0.521$ and $r^2=0.932$ values indicating good predictive ability and reliability. The atomic contribution map analysis of most active compound (compound 7) indicates that hydrogen and oxygen atoms in the side chain of ring A and oxygen atom in side chain of ring C contributes positively to the activity of the compounds. The HQSAR model developed and the atomic contribution map can serve as a guideline in designing new compounds for VEGFR-2 inhibition.

• 농약과학회지
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• 제13권2호
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• pp.117-125
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• 2009

Phenylformamidine계 유도체들은 곤충의 신경전달 물질인 octopamine과 경쟁적으로 octopamine receptor에 작용하여 살충 활성을 나타낸다. 불소를 함유한 4-fluoro-2-methylaniline과 2-fluoro-4-methylaniline을 트리에틸오르토포메이트와 반응시켜 얻은 중간체 formimidate(1)을 마이크로웨이브 조건하에서 반응시켜 짧은 반응시간 내에서 높은 수율로 새로운 화합물인 다양한 N', N'-fluorophenylformamidine 유도체들을 합성하였으며 이들 화합물의 복숭아 흑진딧물, 배추좀나방, 점박이응애, 그리고 벼멸구 등에 대한 살충활성을 시험하였다. 2-I-a, 2-I-c, 2-I-d, 2-II-d 화합물들이 응에류와 멸구유에 좋은 살충활성을 보여주었다.

• 생물정신의학
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• 제13권4호
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• pp.289-298
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• 2006

목 적: 본 연구의 목적은 자폐스펙트럼장애를 가진 아동들과 그 부모로 이루어진 trio를 대상으로 이 장애와 NMDA 수용체 유전자, 그 가운데 GRIN2B 유전자와의 관련성을 규명하고자 하는 것이다. 방 법: 발달지연을 주소로 가천의대 길병원과 경상대학교병원 소아정신과 외래를 내원한 아동을 선별 대상으로 하였다. DSM-IV 진단체계를 이용하여 2명의 소아정신과 의사가 자폐 스펙트럼 장애로 진단한 아동이 일차적인 연구 대상으로 선별되었다. 선별된 아동과 부모들에게는 한국판 자폐증 진단 관찰 스케줄(Autism Diagnostic Observation Schedule, 이하 ADOS) 및 자폐증 진단 면담-개정판(Autism Diagnostic Interview-Revised, 이하 ADI-R)를 실시하였다. PCR-RFLP법을 이용, GRIN2B 유전자에서 모두 4개의 단일 염기 다형성을 분석하였다(rs7301328, rs1806201, rs1805247, rs1805502). 각각의 SNPs에 대한 allelic association 을 평가하기 위하여 TDT 방법이 시행되었으며, 이를 통해 자폐장애 아동이 부모로부터 후보유전자의 특정 alleles들을 유의하게 더 많이 전달받았는지의 여부를 관찰한 뒤 McNemar chi-square test(df=1)에 의거하여 분석하였다. 결 과: 1) 연구 대상군의 특성 : 총 126명의 자폐 스펙트럼장애 아동과 그들의 생물학적 부모가 최종 분석 대상에 포함되었다. 전체 대상자 중 109명(86.5%)이 남아였으며 여아는 17명(13.5%)으로, 남아 대 여아의 비율은 6.41:1이었다. 대상군의 진단 분포는 자폐장애 107명(85.1%), 달리 분류되지 않는 전반적 발달장애(PDD, NOS) 17명(13.5%), 아스퍼거 씨 장애(Asperger's disorder) 2명(1.6%)이었다. 대상군 아동의 평균 연령은 $71.9{\pm}31.6$개월(range : 26~185개월)이었으며 한국판 사회성숙도 검사로 측정된 평균 사회지수(Social Quotient)는 $61.2{\pm}20.6$(range : 23.1~126), 측정 가능한 아동들의 평균 지능은 $65.0{\pm}27.7$(range : 25~126)이었다. K-CARS 점수는 $31.5{\pm}5.4$(range 18.5~46)로 나타났다. 2) 유전자 분석 : 분석한 GRIN2B 유전자의 4개 SNPs 가운데 하나의 SNP(rs1805247)에서 의미 있는 allelic transmission의 차이를 보였다. 이 SNP에서 transmission ratio(transmitted alleles/non-transmitted alleles)는 A allele과 G allele에서 각각 2.03과 .49로, A allele이 G allele에 비해 부모로부터 환자군에게 더 빈번하게 전달(preferential transmission) 되었음이 확인되었다(TDT ${\chi}^2$=12.89, p=.0003). 이는 Bonferroni correction 후에도 여전히 유의미한 수준을 유지하였다(p=.0009). 기타 3개의 SNP(rs7301328, rs1806201, rs1805502) 들에서는 의미 있는 transmission의 차이가 나타나지 않았다(p<.05). 결 론: 본 연구에서 GRIN2B 유전자의 단일유전자 다형성과 자폐스펙트럼장애 사이에 유의한 연관성을 보였다. 이는 glutamate NMDA 2B수용체 유전자가 이 질환의 발생에 관여할 가능성을 시사하는 것이라 생각된다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1999년도 춘계학술대회
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• pp.1-4
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• 1999

The potential therapeutic benefit of nicotinic ligands in a variety of neurodegenerative pathologies involving the CNS has energized research efforts to develop nicotinic acetylcholine receptor (nAChR) subtype-selective ligands. In particular, there has been a concerted effort to develop nicotinic compounds with selectivity for CNS nAChRs as potential pharmacological tools in the management of these disorders. The characterization of other novel nicotinic ligands such as epibatidine. showing a marked increase in potency at nAChRs, has provided additional support for the development of potent, selective ligands at individual nAChR subtypes. We have developed and studied a number of nicotinic compounds to identify potential candidates exhibiting such selectivity. In the present study, we report the synthesis and biological evaluations of some azabicyclic and azatricyclic nicotine analogs to decipher the relationship among steric requirements of the nicotine's pyrrolidine ring system, binding affinity and subtype-selectivity.

• The Korean Journal of Physiology and Pharmacology
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• 제10권5호
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• pp.273-282
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• 2006

The aim of the present study was to investigate the effects of R-(-)-2,10,11-trihydroxy-N-propylnoraporphine [R-(-)-TNPA], a selective agonist of dopaminergic $D_2$ receptor and S(-)-raclopride, a selective antagonist of dopaminergic $D_2$ receptor, on the secretion of catecholamines (CA) evoked by cholinergic stimulation and membrane-depolarization in the isolated perfused model of the rat adrenal gland, and also to establish its mechanism of action. R-(-)-TNPA $(10{\sim}100\;{\mu}M)$ perfused into an adrenal vein for 60 min produced dose- and time-dependent inhibition in CA secretory responses evoked by ACh (5.32 mM), high $K^+$ (56 mM), DMPP $(100\;{\mu}M)$ and McN-A-343 $(100\;{\mu}M)$. R-(-)-TNPA itself did also fail to affect basal CA output. Also, in adrenal glands loaded with R-(-)-TNPA $(30\;{\mu}M)$, the CA secretory responses evoked by Bay-K-8644 $(10\;{\mu}M)$, an activator of L-type $Ca^2+$ channels and cyclopiazonic acid $(10\;{\mu}M)$, an inhibitor of cytoplasmic $Ca^{2+}-ATPase$ were also inhibited. However, S(-)-raclopride $(1{\sim}10\;{\mu}M)$, given into an adrenal vein for 60 min, enhanced the CA secretory responses evoked by ACh, high $K^+$, DMPP and McN-A-343 only for the first period (4 min), although it alone has weak effect on CA secretion. Moreover, S(-)-raclopride $(3.0\;{\mu}M)$ in to an adrenal vein for 60 min also augmented the CA release evoked by BAY-K-8644 and cyclopiazonic acid only for the first period (4 min). However, after simultaneous perfusion of R-(-)-TNP A $(30\;{\mu}M)$ and S(-)-raclopride $(3.0\;{\mu}M)$, the inhibitory responses of R(-)-TNPA $(30\;{\mu}M)$ on the CA secretion evoked by ACh, high $K^+$, DMPP, McN-A-343, Bay-K-8644, and cyclopiazonic acid were significantly reduced. Taken together, these experimental results suggest that R-(-)-TNPA greatly inhibits the CA secretion from the perfused rat adrenal medulla evoked by cholinergic stimulation (both nicotininc and muscarinic receptors) and membrane depolarization, but S(-)-raclopride rather enhances the CA release by them. It seems that this inhibitory of R-(-)-TNPA may be mediated by stimulation of inhibitory dopaminergic $D_2$ receptors located on the rat adrenomedullary chromaffin cells, while the facilitatory effect of S(-)-raclopride is due to the blockade of dopaminergic $D_2$ receptors, which are relevant to extra- and intracellular calcium mobilization. Therefore, it is thought that dopaminergic $D_2$ receptors may be involved in regulation of CA release in the rat adrenal medulla.

• 대한핵의학회지
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• 제20권2호
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• pp.85-100
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• 1986

To evaluate the clinical and pathogenetic roles of TSH receptor antibodies in autoimmune thyroid diseases, TBII were measured by TSH-radioreceptor assay methods in 352 patients with Graves' disease, 108 patients with other thyroid diseases and 69 normal persons. The normal range of TBII activity was less than 15%. The frequencies of detectable TBII in 169 patients with untreated Graves' disease, 31 patients with hyperthyroidism under treatment and 70 patients with euthyrodism under treatment were 92.4%, 87.1% and 54.3% respectively. However 12 (21.8%) out of 55 patients who have been in remission more than one year after discontinuation of antithyroid drugs treatment had detectable TBII activities in their sera. In 196 patients with untreated Graves' disease, the frequency of TBII increased by increasing size of goiter and the frequency of proptosis was significantly high in patients whose TBII activities were more than 60%. TBII activities were roughly correlated with total $T_3,\;T_4$ and free $T_4$ index but low $\gamma^2$ value(less than 0.1). In 67 patients with Graves' disease who were positive TBII before antithyroid drugs treatment, TBII activities began to decrease from the third months and it was converted to negative in 35.8% of patients at 12 months after treatment. There were no significant differences of the declining and disappearing rates of TBII activities between high dose and conventional dose groups. TBII activities were significantly increased initially (2-4 months) and then began to decrease from 5-9 months after $^{131}I$ treatment. There were two groups, one whose TBII activities decreased gradually and the other did not change untill 12 months after subtotal thyroidectomy. Although preoperative clinical and laboratory findings of both groups were not different, TBII activities of non-decreasing group were significantly higher than those of decreasing group$(74.6{\pm}18.6%\;vs\;39.2{\pm}15.2%;\;P<0.01)$. Thirty three(55.9%) out of 59 patients with Graves' disease relapsed within 1 year after discontinuation of antithyroid drugs. The positive rate of TBII at the end of antithyroid drug treatment in relapse group(n=33) was significantly higher than those in remission group (n=26) (63.6% vs 23.1%; P < 0.05). The mean value of TBII activities at the end of antithyroid drug treatment in relapse group was significantly elevated $(29.7{\pm}21.4%\;vs\;14.7{\pm}11.1%,\;P<0.05)$. Positive predictive value of TBII for relapse was 77.8%, which was not different from those of TRH nonresponsiveness(78.6%). The frequencies of detectable TBII in 68 patients with Hashimoto's thyroiditis, 10 patients with painless thyroiditis and 5 patients subacute thyroiditis were 14.7%, 20% and 0%, respectively. However in 25 patients with primary nongoitrous myxedema, 11 patients(44%) showed TBII activities in their sera. 9 out of 11 patients who had TBII activities in their sera showed high TBII activities(more than 70% binding inhibition) and their IgG concentrations showing 50% binding inhibition of $^{125}I-bTSH$ to the TSH receptor were ranges of 0.1-2.6 mg/dl. One patient who had high titer of TBII in her serum delivered a hypothyroid baby due to transplacental transfer of maternal TBII. These findings suggested that 1) TSH receptor antibodies are closely related to a pathogenetic factor of Graves' hyperthyroidism and of some patients with primary non-goitrous myxedema, 2) measurement of TSH receptor antibodies is helpful in evaluating the clinical outcome of patients with Graves' disease during antithyroid drug treatment and in predicting the neonatal transient hypothyroidism of baby delivered from primary myxedema patients. 3) there are 2 or more different types of TSH receptor antibodies in autoimmune thyroid diseases including one which stimulates thyroid by binding to the TSH receptor and another which blocks adenylate cyclase stimulation by TSH.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제12권2호
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• pp.179-191
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• 2001

연구목적：신생아의 행동 특성과 DAT1, DRD2, DRD3 및 DRD4 유전자 다형성 사이에 연관이 있는지 평가하였다. 방 법：2000년 4월 17일부터 2000년 6월 17일까지 출생한 정상 신생아 114명을 대상으로 하였다. 신생아 행동 평가는 Neonatal Behavioral Assessment Scale(NBAS)을 이용하여 생후 약 18시간에 평가하였으며, 출산시 제대혈액을 채취하여 DAT1, DRD2, DRD3 및 DRD4 유전자 다형성을 검사하였다. DAT1, DRD2, DRD3 및 DRD4 유전자의 유전자형에 따라서 집단 사이에 NBAS 7개 항목 점수를 비교하였다. 결 과：DAT1 유전자는 10/10 유전자형 집단과 비교해서 기타 유전자형 집단이 사회성-상호작용, 상태 조직력 및 상태 조절 능력 항목에서 유의하게 점수가 높았다. DRD2 유전자 Ser311/Cys311 유전자형은 Ser/Ser 유전자형 집단과 기타 유전자형 집단 사이에 NBAS 항목 점수에 유의한 차이가 없었다. DRD2 유전자는 TaqI A 및 TaqI B 유전자형에 의한 집단 사이에 NBAS 항목 점수에 유의한 차이가 없었다. DRD3 유전자는 유전자형에 의한 집단 사이에 NBAS 항목 점수에 유의한 차이가 없었다. DRD4 유전자 promoter 유전자형에 의한 집단 사이에 NBAS 항목 점수에 유의한 차이가 없었다. DRD4 유전자 반복배열이 긴 유전자형 집단은 짧은 유전자형 집단보다 습관화 항목 점수가 유의하게 높았다. 결 론：이러한 성적은 DAT1 및 DRD4 유전자 반복배열 다형성이 신생아 행동 특성에 영향을 미치는 유전적 기전일 가능성을 시사한다.