• 약학회지
• /
• 제36권5호
• /
• pp.496-505
• /
• 1992

The correlation between GABA receptors($GABA_A$ and $GABA_B$ receptor) and benzodiazepine receptor on the saline infusion-induced micturition reflex contraction was studied in the female rat. To investigate the effect of ${\gamma}-aminobutyric$ acid(GABA) on the micturition reflex, exogenous GABA(10 mg/kg) and GABA transaminase inhibitor(aminooxyacetic acid; AOAA $1\;{\mu}g$) were administered intravenously(i.v.) and intracerebroventriculary(i.c.v.), respectively. In result, both GABA and AOAA inhibited the saline induced micturition reflex contraction. This AOAA induced inhibition of micturition reflex was blocked by both bicuculine. $GABA_A$ receptor antagonist, and Ro 15-1788, benzodiazepine receptor antagonist. Muscimol, $GABA_A$ receptor antagonist($0.1\;{\mu}g$ i.c.v., $3\;{\mu}g$ intrathecal; i.t., 1 mg/kg i.v.) and baclofen, $GABA_A$ receptor agonist($1\;{\mu}g$ i.c.v., $3\;{\mu}g$ i.t., 1 mg/kg i.v.) also inhibited the bladder contraction. Pretreatment of bicuculline($1\;{\mu}g$ i.c.v.), but not of 5-aminovaleric acid(AVA, $1\;{\mu}g$ i.c.v.), $GABA_B$ receptor antagonist blocked the central inhibition of muscimol. These inhibitory effects were reversed by Ro15-1788 but were potentiated by flurazepam, benzodiazepine receptor antagonist. On the other hand, the inhibitory effects of baclofen were not affected by Ro 15-1788. Diazepam and flurazepam also inhibited the micturition reflex contraction when they were administered $3\;{\mu}g$ i.c.v., $10\;{\mu}g$ i.t., $10\;{\mu}M$, $30\;{\mu}M$ transurethrally, respectively. In conclusion, these results suggest that the micturition reflex is mediated by $GABA_A$, $GABA_B$ receptor and benzodiazepine receptor. The bezodiazepines increase the receptor binding of GABA to the $GABA_A$ receptor, so that the benzodiiazepines show the synergistic effect on the inhibition of the micturition reflex contraction, but not to the $GABA_B$ receptor.

• Biomolecules & Therapeutics
• /
• 제13권3호
• /
• pp.138-142
• /
• 2005

Adenosine and GABA are known to be major inhitory neurotransmitters in the central nervous system and its receptors mediate various neurophamacological effects including cardiovascular modulatory effects. Inhibitory cardiovascular effects induced by intrathecal (i.t.) administration of adenosine $A_1$ receptor agonist and its modulation by cyclic AMP was suggested by our previous report. In this experiment, we examined the modulation of cardiovascular effects of adenosine $A_1$ receptor and adenosine $A_2$ receptor by $GABA_B$ receptors antagonist in the spinal cord. I.t. administration of 10 nmol of $N^6$-cyclohexyladenosine (CHA, an adenosine $A_1$ receptor agonist), I.t. administration of 2 nmol of 5'-(N-cyclopropyl)-carboxamidoadenosine (CPCA, an adenosine $A_2$ receptor agonist), pretreatment with 5-aminovaleric acid (a $GABA_B$ receptor antagonist, 50 nmol, i.t.) prior to administration of CHA and pretreatment with 5-aminovaleric acid (a $GABA_B$ receptor antagonist, 50 nmol, i.t.) prior to administration of CPCA were performed in anesthetized, artificially ventilated Sprague-Dawley rats. I.t. administration of 50 nmol of 5-aminovaleric acid significantly attenuated the inhibitory cardiovascular effects of CHA but did not attenuated the inhibitory cardiovascular effects of CPCA. It is suggested that cardiovascular responses of adenosine $A_1$ receptor is modulated by $GABA_B$ receptor and adenosine $A_2$ receptor is not modulated by $GABA_B$ receptor in the spinal cord.

• 한국미생물·생명공학회지
• /
• 제31권2호
• /
• pp.117-123
• /
• 2003

공시균인 Saccha. erythraea IFO 13426으로부터 VB-C에 의한 erythromycin 생산 유도능이 시사된 바 있으므로, 공시균으로부터 VB-C와 특이적으로 결합하는 autoregulators 및 receptor gene을 탐색하여, EM의 생산 조절 기구를 규명하고자 하였다. 탐색의 일환으로 기존의 Streptomyce속 receptor gene의 공통배열을 primer로 이용하여 PCR을 수행하였고, 예상 크기인 120bp의 단편을 pUC19 vector에 ligation하여 E. coli DH5$\alpha$에 형질전환한 후, plasmid를 분리하여 BamHI을 처리하여 2% agarose gel에 전기영동한 결과, pUC19 (2.7kbp)외에 receptor gene PCR 산물이 120bp위치에 존재하는 것을 확인하였다. 형질전환된 plasmid로 PCR을 수행하여 염기배열을 결정한 후 해석한 결과 Streptomyces sp. 유래의 receptor gene과 유사함을 확인하였다. 따라서 Saccha. erythraea IFO 13426에는 항생물질인 erythromycin의 생산에 관여한다고 추정되는 autoregulator receptor protein을 코드하는 유전자가 존재할 것으로 예상되어 120 bp의 PCR product를 probe로 이용하여 Southern 및 colony hybridization을 통하여 3.2 kbp의 SacI 단편을 가지는 plasmid(pESG)를 제작하였고, 이를 sequencing한 결과, autoregulator receptor protein 유전자가 KpnI과 SalI을 포함하는 영역에 존재한다는 것을 알 수 있었으며 이를 EsgR이라 명명하였다. 유전자 해석 결과, EsgR은 205개의 아미노산으로 구성되어 있으며, 이는 기존의 autoregulator receptor proteins과 비교시 30%이상의 상동성을 나타내었으며, 기존의 autoregulator receptor prorein들이 하부의 항생물질 생합성 유전자들의 제어를 위해 보유하고 있는 helix-turn-helix DNA binding motif를 EsgR이 보유하고 있는 점에서, EsgR은 Saccha. erythraea가 보유하는 autoregulator receptor protein을 code하는 유전자로 추정되었다.

• 생물정신의학
• /
• 제12권2호
• /
• pp.107-113
• /
• 2005

Purpose:In an attempt to predict the interpersonal differences of therapeutic response to antipsychotic drugs on pharmaco-genetic bases, this study was designed to investigate the relationship between the therapeutic response to antipsychotic drugs and Taq I A dopamine $D_2$ receptor polymorphism in schizophrenic patients. Methods:The subjects were 158 patients diagnosed with schizophrenia(DSM-IV). The therapeutic response to antipsychotic drugs was evaluated using the Treatment Response Scale(TRS) retrospectively. Patients were divided into two groups, dopamine receptor antagonist responders, and serotonin-dopamine antagonist responders. The patients' Taq I A dopamine $D_2$ receptor polymorphism was determined by polymerase chain reaction(PCR) and restriction fragment length polymorphism(RFLP). Results:The dopamine receptor antagonist responders had the A1 allele in significantly higher incidences (${\chi}^2$(1)=4.875, p=0.027, two-tailed). No significant difference was found among the serotonin-dopamine antagonist responders between those with or without the A1 allele. Conclusions:The patients with the A1 allele responded better to dopamine receptor antagonists than those with no A1 allele. Based on these results, it is suggested that the pharmacological effect of dopamine receptor antagonists can be predicted depending on the presence of the A1 allele in schizophrenic patients.

• BMB Reports
• /
• 제30권1호
• /
• pp.1-6
• /
• 1997

The ability of Hep-G2 cells to process $[^{125}I]LDL$ under basal conditions was investigated. The receptor-binding and internalization of $[^{125}I]LDL$ increased with the time of incubation in a saturable manner. After 4 h of incubation, 31.4 ng of $[^{125}I]LDL$ was cell bound. The cells rapidly internalized $[^{125}I]LDL$ via specific, receptor-mediated endocytosis. The amount of internalized $[^{125}I]LDL$ reached a maximun of 96.7 ng at 2 h of incubation and remained constant for the next 2 h. The rate of degradation of internalized $[^{125}I]LDL$ proceeded in a linear manner over the entire 4 h of incubation after an initial lag period. The effects of individial fatty acids (C18:0. C18:1, C18:2. and C18:3), differing in their degree of unsaturation. on the receptor-binding, internalization and degradation of $[^{125}I]LDL$ were also investigated. Inclusion of 1.0 mM of each fatty acid into the culture medium significantly increased $[^{125}I]LDL$ metabolism in Hep-G2 cells. Among the fatty acids tested, stearic acid had the least effect on the receptor-binding activity. There were no significant differences among the unsaturated fatty acids in LDL-receptor binding. The effect of individual fatty acids on the $[^{125}I]LDL$ uptake was similar to that of the receptor-binding. showing a significantly lower effect with stearic acid. The amount of degraded material of internalized $[^{125}I]LDL$ was the lowest with stearic acid when it was compared with unsaturated fatty acids.

• Animal cells and systems
• /
• 제7권2호
• /
• pp.145-149
• /
• 2003

Adult periodontitis is a chronic inflammatory disease whose etiology is not well defined. Recent studies have shown that vitamin D receptor gene has been a candidate for the susceptibility of adult periodontitis. The purpose of this study is to investigate the frequency of Taq I restriction fragment length polymorphism (RFLP) in the vitamin D receptor gene in nan periodontically healthy controls and 28 adult periodontitis patients. Taq I RFLP in the vitamin D receptor gene was detected by PCR amplification, followed by restriction enzyme digestion and 2％ agarose gel electrophoresis. There was no significant difference in the distribution of Taq I RFLP between healthy controls and adult periodontitis group (P > 0.05). Thus, Taq I RFLP in the vitamin D receptor gene may not confer the susceptibility to adult periodontitis in Korean population. However, t allele distributions of this RFLP showed various frequencies among ethnic groups studied. Further studies in other ethnic groups will be required.

• 생명과학회지
• /
• 제21권4호
• /
• pp.481-485
• /
• 2011

T0901317은 핵수용체 전사인자인 liver X receptor (LXR, NR1H2/3)의 강력한 합성 리간드이다. 그러나, T0901317은 farnesoid X receptor (FXR, NR1H4)와 pregnane X receptor (PXR, NR1I2)에 대해 작용물질(agonist) 로, androgen receptor (AR, NR3C4)와 rertinoid-related orphan receptor-${\alpha}$ (ROR-${\alpha}$, NR1F1)에 대해 길항제(antagonist)로 작용하여, LXR외에 적어도 다른 4종의 핵수용체에 대해 그 활성을 조절한다고 보고되었다. 우리는 T0901317이 또 다른 핵수용체인 constitutive androstane receptor (CAR, NR1I3)에 대해 저해제로 기능함을 확인 하였다. CAR는 이미 T0901317에 의해 기능이 조절된다고 알려진 PXR, FXR, LXR과 더불어 간에서 생체이물과 콜레스테롤의 대사작용에 중요한 역할을 하므로 T0901317에 의해 CAR의 활성이 조절된다는 사실은, 간세포에서 T0901317을 이용한 실험 결과를 해석할 때 세포 내에 이미 존재하는 이들 핵수용체 단백질의 영향을 고려하여 주의깊게 해석해야 함을 의미한다.

• Journal of Animal Science and Technology
• /
• 제50권5호
• /
• pp.649-656
• /
• 2008

본 연구는 insulin-like growth factors(IGFs)가 돼지 지방전구세포의 증식과 분화에 미치는 작용기전을 구명하기 위해서 수행하였다. 지방전구세포는 갓난 암퇘지의 등지방에서 분리하였고, serum-deprived 조건하에서 IGFs와 mutant IGFs를 함유시켜 배양했는데 이 mutant IGFs는 IGF-Ⅰ에 비해 type-1 IGF receptor와 insulin receptor에 대한 친화력이 낮다. 50ng/ml의 IGF-Ⅰ, [Leu60]IGF-I, IGF-Ⅱ 및 [Leu27]IGF-Ⅱ를 배양중인 세포에 4일동안 처리했다. IGF-Ⅰ, [Leu60]IGF-I, IGF-Ⅱ 및 [Leu27]IGF-Ⅱ는 돼지 지방전구세포의 증식을 각각 39%, 8%, 25% 및 2% 촉진했다(증가된 세포수에 의해 측정). 이 사실은 IGF-Ⅰ과 IGF-Ⅱ는 type-1 IGF receptor 또는 insulin receptor에 결합을 통해서 지방세포의 증식 촉진을 가져왔음을 나타낸다. 그리고 IGF-Ⅰ, [Leu60]IGF-I, IGF-Ⅱ 및 [Leu27] IGF-Ⅱ는 지방전구세포의 분화를 50%, 17%, 37% 및 30% 각각 촉진시켰다(세포 분화는 glycerol- phosphate dehydrogenase 활성도에 의해 측정했다). IGF-Ⅰ의 type-1 IGF receptor 또는 insulin receptor에의 친화력이 낮아져서 세포 분화 촉진작용을 감소시킨 것이다. 그러나 [Leu27] IGF-Ⅱ의 분화촉진 작용은 IGF-Ⅱ의 그것에 비해 크게 차이가 나지 않았는데, 이 사실은 IGF-Ⅰ과 IGF-Ⅱ는 서로 다른 수용체－매개 작용기전에 의해 세포분화를 촉진시킴을 나타낸다. 즉 IGF-Ⅱ는 type-1 IGF receptor 또는 insulin receptor가 관여하지 않는 작용을 통해 돼지 지방전구세포의 분화를 촉진시켰다. 이 작용은 IGF-Ⅱ가 type-2 IGF receptor(또는 cation- independent mannose-6 phosphate receptor [CIM6P /IGF2 receptor])에 결합을 통해서 이뤄지는 것으로 여겨진다. 위의 결과는 IGF-Ⅱ가 CIM6P/ IGF2 receptor에의 결합을 통해 동물 지방전구세포의 분화를 촉진시킨다는 것을 밝혀낸 최초의 연구이다. 요약하면 이 본 연구는 IGF-Ⅰ과 IGF-Ⅱ는 서로 다른 세포내 receptor가 관여하는 작용기전을 통해 돼지 지방전구세포의 분화를 촉진함을 보여준다.

• Journal of Microbiology and Biotechnology
• /
• 제25권2호
• /
• pp.247-254
• /
• 2015

In this presentation, I describe the expression and purification of the recombinant liver X receptor β-ligand binding domain proteins in E. coli using a commercially available double cistronic vector, pACYCDuet-1, to express the receptor heterodimer in a single cell as the soluble form. I describe here the expression and characterization of a biologically active heterodimer composed of the liver X receptor β-ligand binding domain and retinoid X receptor α-ligand binding domain. Although many of these proteins were previously seen to be produced in E. coli as insoluble aggregates or "inclusion bodies", I show here that as a form of heterodimer they can be made in soluble forms that are biologically active. This suggests that co-expression of the liver X receptor β-ligand binding domain with its binding partner improves the solubility of the complex and probably assists in their correct folding, thereby functioning as a type of molecular chaperone.

• 대한약리학회지
• /
• 제30권1호
• /
• pp.49-57
• /
• 1994

Oxomemazine이 muscarinic receptor subtypes에 대하여 선택성을 가지는지에 관한 지견을 얻고자, 대뇌, 심실 및 회장 muscarinic receptor에 대한 oxomemazine의 결합성질을 조사, 비교하였다. $[^3H]QNB$ 포화결합실험 결과 세 조직의 muscarinic receptor는 $[^3H]QNB$에 대해서는 affinity가 약 60pM인 단일 receptor인 것으로 추정되었다. 대뇌에서 pirenzepine과 oxomemazine의 $[^3H]QNB$ 결합억제에 대한 Hill coefficient는 각각 0.67 및 0.8로서 대뇌에는 이들 약물에 대하여 affinity가 서로 다른 두 종류의 muscarinic receptor subtypes가 존재하는 것으로 나타났으며, pirenzepine에 대한 high $affinity(M_1)$와 $low affinity(M_2)$ receptor 및 oxomemazine에 대한 high $affinity(O_H)$와 $low\;affinity (O_L)$ receptor의 분포비는 약 60:40 및 40:60이었고, $M_1$과 $M_2$ receptor에 대한 pirenzepine의 $K_i$치는 16nM 및 431 nM, $O_H$와 $O_L$, receptor에 대한 oxomemazine 의 $K_i$치는 80nM 및 1350nM이었다. 그러나 심실과 회장에서 이들 약물의 $[^3H]QNB$ 결합억제에 대한 Hill coefficient는 1에 가까웠다. 심실과 회장 muscarinic receptor에 대한 pirenzepine의 $K_i$치는 850nM 및 250nM, oxomemazine의 $K_i$치는 1460nM 및 670nM로서 대피에서 이들 약물의 low affinity receptor에 대한 $K_i$치에 가까웠다. 즉, muscarinic receptor에 대한 affinity면에서 oxomemazine은 pirenzepine과 같이 대뇌에서 가장 높았으며, 회장에 대해서는 중등도였고, 심실에서 가장 낮았다. 이로 보아 oxomemazine은 $M_1\;receptor$에 선택성이 있는 것으로 추정된다.