• 대한약리학회지
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• 제31권3호
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• pp.355-363
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• 1995

Calcium수송에 대한 기전을 추구하기위하여, carbachol을 사용하여 ml muscarinic receptor-transfected RBL-2H3 cell-line에서 다음과 같은 실험결과를 얻었기에 이에 보고한다. 1) Carbachol의 투여로 이들 cell-line에서 $Ca^{2+}$ influx가 농도에 따라 증가하였고, hexosaminidase 분비양도 의의있게 증가하였다. 2) Atropine 투여로 Carbachol의 상승작용이 의의있게 억제되었다. 3) 수종의 금속양이온을 투여하여 carbachol의 $Ca^{2+}$수송에 대한 영향을 관찰한 바, 이들 금속이온들은 $Ca^{2+}$의 influx를 의의있게 억제하였다. 4) PMA(20 nM) 투여로 carbachol의 hexosaminidase의 분비는 억제되지 못했지만 $Ca^{2+}$ influx는 억제되었다. 5) PTx $(0.2\;{\mu}g/ml)$ 투여로 carbachol의 hexosaminidase 분비가 의의있게 억제되었다. 위의 결과로 미루어 보아, 이 세포의 muscarinic receptor가 calcium channel을 통한 calcium수송에 매우 중요한 영향을 나타내는데, 이들 calcium ion channel은 적어도 두 종류가 존재하며, 하나는G-protein-dependent calcium channel에 의하며, 다른 하나는 G-protein-independent calcium channel에 대한 작용에 의한 것으로 생각된다. 또한 이 calcium channel들은 2가 또는 3가의 다른 금속 ion들에 의하여 calcium수송이 억제된다.

• The Korean Journal of Physiology and Pharmacology
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• 제16권6호
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• pp.437-446
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• 2012

Ulcerative colitis is an inflammatory bowel disease (IBD) characterized by recurrent episodes of colonic inflammation and tissue degeneration in human or animal models. The contractile force generated by the smooth muscle is significantly attenuated, resulting in altered motility leading to diarrhea or constipation in IBD. The aim of this study is to clarify the altered contractility of circular and longitudinal smooth muscle layers in proximal colon of trinitrobenzen sulfonic acid (TNBS)-induced colitis mouse. Colitis was induced by direct injection of TNBS (120 mg/kg, 50% ethanol) in proximal colon of ICR mouse using a 30 G needle anesthetized with ketamin (50 mg/kg), whereas animals in the control group were injected of 50% ethanol alone. In TNBS-induced colitis, the wall of the proximal colon is diffusely thickened with loss of haustration, and showed mucosal and mucular edema with inflammatory infiltration. The colonic inflammation is significantly induced the reduction of colonic contractile activity including spontaneous contractile activity, depolarization-induced contractility, and muscarinic acetylcholine receptor-mediated contractile response in circular muscle layer compared to the longitudinal muscle layer. The inward rectification of currents, especially, important to $Ca^{2+}$ and $Na^+$ influx-induced depolarization and contraction, was markedly reduced in the TNBS-induced colitis compared to the control. The muscarinic acetylcholine-mediated contractile responses were significantly attenuated in the circular and longitudinal smooth muscle strips induced by the reduction of membrane expression of canonical transient receptor potential (TRPC) channel isoforms from the proximal colon of the TNBS-induced colitis mouse than the control.

• Journal of Applied Biological Chemistry
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• 제63권4호
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• pp.365-373
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• 2020

We previously reported the potential of Senna tora L. seeds fermented by Lactobacillus casei (FSL) as a laxative agent in a loperamide-induced constipation rat model. Here, we examine the mechanism of action of FSL and its bioactive compound, revealed herein, on loperamide-induced constipation Sprague Dawley rat model. We identified the compound aurantio-obtusin (AO) using HPLC quantitative analysis. Rats were randomly assigned to six experimental groups (eight rats each)-normal and constipated groups (loperamide, FSL [100, 300, 500 mg/kg], and AO [1 mg/kg]). The FSL and AO-treated group showed an increase in the frequency, amount, and water content of feces in the constipated rat. Moreover, FSL and AO increased the intestinal transit speed in the constipated rat. Histological analysis revealed that FSL and AO recovered the intestinal mucus, the number of goblet cells, as well as thickness of the mucosa layer and muscle. Furthermore, the protein levels of the muscarinic acetylcholine receptor M3, which is involved in intestine contraction, were recovered in the FSL and AO-treated group. Its downstream signaling pathway (p-protein kinase C) was recovered by FSL and AO treatment. In conclusion, fermentation of S. tora L. seeds increases AO, which improves intestinal function, indicating that FSL is effective for treating constipation.

• Biomolecules & Therapeutics
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• 제7권4호
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• pp.307-314
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• 1999

The human muscarinic acetylcholine receptor (mAChR) subtypes Hml, Hm2 and Hm3 have been expressed in insect cells (Spodoptera frugiperda, Sf9) using the baculovirus expression system. Expression of relevant DNA, transcript and receptor proteins was identified by PCR, Northern blotting and [$^{3}H$]QNB binding, respectively. As assessed by [$^{3}H$]QNB binding sites, yields of muscarinic receptors in membrane preparations in this study were as about 5-20 times high as those in mammalian cells reported in previous studies. The [$^{3}H$]QNB competition binding studies with well-known subtype-selective mAChR antagonists showed that the receptors expressed in Sf9 cells retain the pharmacological characteristics expected for the ml , m2 and m3 muscarinic receptors. The ml-selective antagonist, pirenzepine, displayed a considerably higher affinity for Hml by 110-fold and 35-fold than for Hm2 and Hm3, respectively, The m2-selective methoctramine displayed a significantly higher affinity for Hm2 than for Hml and Hm3 (10- and 26-fold, respectively). p-F-HHSiD exhibited high affinity for Hm3 that is not significantly different from those for Hml, but 66-fold higher than its affinity for Hm2. The functional coupling of the recombinant receptors to second messenger systems was also examined. While both Hml and Hm3 stimulated phosphoinositide hydrolysis upon activation by carba-chol, Hm2 produced no response. On the other hand, activation of mAChRs induced the inhibition of forsko-lin-stimulated cyclic AMP formation in Hm2-expressing cells, whereas the significant dose-dependent increase in or poor response on cyclic AMP formation were produced in Hml or Hm3-expressing cells, respectively. These results indicate the differential coupling of recombinant Hml, Hm2 and Hm3 receptors expressed in SF9 cells to intracellular signalling system.

• Journal of Yeungnam Medical Science
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• 제12권2호
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• pp.246-259
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• 1995

배뇨근의 운동성에 대한 baclofen의 억제작용의 기전을 탐구하기 위하여 다음과 같은 실험을 하였다. 흰쥐 (Sprague-Dawley)의 방광에서 적출한 배뇨근절편을 적출근편실험조에 현수하고, 등척성 장력측정기를 사용하여 그 수축력을 묘기하였다. 실험조내의 영양액의 온도는 $37^{\circ}C$로 유지시키고, 95% 산소와 5% 이산화탄소의 혼합기체를 공급하여 pH를 7.4로 유지하였다. 배뇨근절편은 전기장자극에 의해 수축하였는데, 8분간의 전기장자극 유발수축 중 최초의 급격한 수축반응은 mATP와 baclofen에 의해 약간 억제되는 경향을 보였으며, 후기 4분간의 수축반응은 콜린성 무스카린성 수용체 봉쇄제인 atropine과 $GABA_B$ 수용체 효현제인 baclofen에 의해 유의하게 억제되었다. Atropine은 배뇨근 절편의 acetylcholine 유발 수축을 길항하였고, mATP는 ATP 유발 수축을 완전히 봉쇄하였으나, baclofen 존재하에서는 acetylcholine이나 ATP 첨가에 의한 배뇨근의 수축이 영향을 받지 않았다. 이상의 결과를 종합하면, 흰쥐 방광에는 $GABA_B$ 수용체가 존재하며 baclofen은 이 수용체를 통하여 콜린성신경 말단에서의 신경전달체의 유리를 억제하여 배뇨근의 수축성을 감소시킨다고 사료된다.

• Tuberculosis and Respiratory Diseases
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• 제49권4호
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• pp.486-494
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• 2000

연구배경 : 부교감 신경의 자극에 의해 유발된 기관지 수축은 $M_2$ 무스카린성 수용체(muscarinic receptors)에 의해 억제된다. 기관지 과민성을 유발시킨 동물 모델에서는 아세틸콜린 분비를 억제하는 $M_2$ 무스카린성 수용체 기능이 손상되어 아세틸콜린의 분비가 증가되고, 이로 인해 기관지 과민성을 나타낸다. 본 연구에서는 경증, 중등증, 중증 천식 환자를 대상으로 $M_2$ 무스카린성 수용체 기능 이상이 있는지 여부와 천식의 중증도에 따라 $M_2$ 무스카린성 수용체 기능에 차이가 있는지를 알아보고자 연구를 시행하였다. 대상 및 방법 : 고려대학교 안암병원 내과에서 천식으로 진단 받은 27명을 대상으로 하였다. 이 중 경증 천식이 11명, 중등증 천식이 8명, 중증 천식 8명이었다. 천식 발작이 있거나, 2주 이내에 상기도 감염이 있는 환자, 메타콜린 유발 검사에서 음성($PC_{20}{\geq}$16mg/ml)인 환자는 제외하였다. 대상 환자들은 메타콜린 유발 검사를 시행하여 $PC_{20}$을 구하고, 1주일 후에 $M_2$ 무스카린성 수용체 촉진제(agonist) 인 필로카핀(pilocarpine) $180{\mu}g$을 흡입한 후 1차 때와 같은 방법으로 $PC_{20}$을 구해 두 값을 비교하였다. 결과 : 대상 환자의 평균 연령은 39.3$\pm$12.3세였다. 천식의 중증도에 따라 결과를 분석해 보면 경증 천식 환자는 필로카핀 흡입 전 $PC_{20}$은 5.30$\pm$5.23mg/ml(평균$\pm$표준편차)에서 필로카핀 흡입 후 20.82$\pm$22.56mg/ml이었으며(p=0.004), 중등증 천식 환자는 필로카핀 흡입 전 $PC_{20}$은 2.79$\pm$1.51mg/ml에서 필로카핀 흡입 후 4.67$\pm$3.53mg/ml(p=0.012)로 유의하게 증가하였다. 이는 필로카핀에 대한 $M_2$ 무스카린성 수용체 기능이 정상임을 말해준다. 그러나 중증 천식 환자는 필로카핀 흡입 전 $PC_{20}$은 1.76$\pm$1.50mg/ml에서 필로카핀 흡입 후 3.18$\pm$4.03mg/ml(p=0.161)로 필로카핀 흡입 후에 통계적으로 유의한 차이가 없었다. 이는 중증 천식에서는$M_2$ 무스카린성 수용체 기능 이상이 있음을 말해준다. 결론 : 경증, 중등증, 중증을 대상으로 $M_2$ 무스카린성 수용체 기능을 조사해본 결과 경증과 중등증 천식에서는 $M_2$ 무스카린성 수용체 기능 이상이 없었고, 중증 천식에서는 $M_2$ 무스카린성 수용체 기능 이상이 있었다. 이는 천식의 중증도에 따라 $M_2$ 무스카린성 수용체 기능에 차이가 있음을 말해준다.

• Biomolecules & Therapeutics
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• 제27권1호
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• pp.101-106
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• 2019

Most diabetic patients experience diabetic mellitus (DM) urinary bladder dysfunction. A number of studies evaluate bladder smooth muscle contraction in DM. In this study, we evaluated the change of bladder smooth muscle contraction between normal rats and DM rats. Furthermore, we used pharmacological inhibitors to determine the differences in the signaling pathways between normal and DM rats. Rats in the DM group received an intraperitoneal injection of 65 mg/kg streptozotocin and measured blood glucose level after 14 days to confirm DM. Bladder smooth muscle contraction was induced using acetylcholine (ACh, $10^{-4}M$). The materials such as, atropine (a muscarinic receptor antagonist), U73122 (a phospholipase C inhibitor), DPCPX (an adenosine $A_1$ receptor antagonist), udenafil (a PDE5 inhibitor), prazosin (an ${\alpha}_1$-receptor antagonist), papaverine (a smooth muscle relaxant), verapamil (a calcium channel blocker), and chelerythrine (a protein kinase C inhibitor) were pre-treated in bladder smooth muscle. We found that the DM rats had lower bladder smooth muscle contractility than normal rats. When prazosin, udenafil, verapamil, and U73122 were pre-treated, there were significant differences between normal and DM rats. Taken together, it was concluded that the change of intracellular $Ca^{2+}$ release mediated by PLC/IP3 and PDE5 activity were responsible for decreased bladder smooth muscle contractility in DM rats.

• Nutrition Research and Practice
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• 제17권2호
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• pp.192-205
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• 2023

BACKGROUND/OBJECTIVES: It is known that the renin-angiotensin system (RAS) in the brain could regulate cognitive functions as well as blood pressure. Inhibition of RAS for the improvement of cognitive function may be a new strategy, but studies so far have mostly reported on the effects of RAS inhibition by drugs, and there is no research on cognitive improvement through RAS inhibition of food ingredients. Therefore, this study investigated the effect of curcumin on blood pressure and cognitive function and its related mechanism in spontaneously hypertensive rat/Izm (SHR/Izm). MATERIALS/METHODS: Six-week-old SHR/Izm rats were divided into 5 groups: control group (CON), scopolamine group (SCO, drug for inducing cognitive deficits), positive control (SCO and tacrine [TAC]), curcumin 100 group (CUR100, SCO + Cur 100 mg/kg), and curcumin 200 group (CUR200, SCO + Cur 200 mg/kg). Changes in blood pressure, RAS, cholinergic system, and cognitive function were compared before and after cognitive impairment. RESULTS: The SCO group showed increased blood pressure and significantly reduced cognitive function based on the y-maze and passive avoidance test. Curcumin treatments significantly improved blood pressure and cognitive function compared with the SCO group. In both the CUR100 and CUR200 groups, the mRNA expressions of angiotensin-converting enzyme (ACE) and angiotensin II receptor type1 (AT1), as well as the concentrations of angiotensin II (Ang II) in brain tissue were significantly decreased. The mRNA expression of the muscarinic acetylcholine receptors (mAChRs) and acetylcholine (ACh) content was significantly increased, compared with the SCO group. CONCLUSIONS: The administration of curcumin improved blood pressure and cognitive function in SCO-induced hypertensive mice, indicating that the cholinergic system was improved by suppressing RAS and AT1 receptor expression and increasing the mAChR expression.

• 대한약리학회지
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• 제24권2호
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• pp.189-195
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• 1988

인체 정관 평활근에서 각종 자율신경전달체 수용체의 유무를 조사하고 benzodiazepine계의 진정-항불안제인 diazepam이 평활근 운동성에 미치는 작용을 관찰하기 위하여, 32내지 45세의 건강한 지원자로부터 정관절편을 얻었다. 정관 절제술은 국소마취하에 시행되었고, 정관절편의 수축력 측정은 등장성장력측정기에 의하였다. 적출장기실험조 내에서 정관절편의 자율수축은 관찰되지 않았으나, norepinephrine에 대한 반응성은 $33^{\circ}C$에서 가장 예민하였던 바, 이 norepinephrine에 의한 농도의존적 수축력증가작용은 알파-아드레날린성 차단제인 phentolamine에 의해 억제되었다. 또 인체 정관절편은 본 실험의 조건하에서 isoproterenol 의하여 수축하였고, 이 수축작용은 베타-아드레날린성 차단제인 propranolol 의하여 완전히 제거되었다. 동시에 인체 정관절편은 acetylcholine에의해서도 비교적 강하게 수축하였고, 이 수축작용은 콜린성 무스카린성 차단제인 atropine에 의하여 완전히 억제되었다. Diazepam은 norepinephrine에 의한 수축을농도 의존적으로 억 제 하였다. 이상의 결과를 종합하면, 인체 정관 평활근은 체온보다 낮은 $33^{\circ}C$에서 그 활동성이 가장 강하고, 자율신경에 대하여서는 아드레날린성 및 콜린성 수용체가 공존하고 있으며, diazepam은 그 수축력을 약화시킨다고 사료된다.

• The Korean Journal of Physiology and Pharmacology
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• 제24권6호
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• pp.517-527
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• 2020

Layer 2/3 pyramidal neurons (L2/3 PyNs) of the cortex extend their basal dendrites near the soma and as apical dendritic tufts in layer 1, which mainly receive feedforward and feedback inputs, respectively. It is suggested that neuromodulators such as serotonin and acetylcholine may regulate the information flow between brain structures depending on the brain state. However, little is known about the dendritic compartment-specific induction of synaptic transmission in single PyNs. Here, we studied layer-specific serotonergic and cholinergic induction of long-term synaptic plasticity in L2/3 PyNs of the agranular insular cortex, a lateral component of the orbitofrontal cortex. Using FM1-43 dye unloading, we verified that local electrical stimulation to layers 1 (L1) and 3 (L3) activated axon terminals mostly located in L1 and perisomatic area (L2/3). Independent and AMPA receptor-mediated excitatory postsynaptic potential was evoked by local electrical stimulation of either L1 or L3. Application of serotonin (5-HT, 10 μM) induced activity-dependent longterm depression (LTD) in L2/3 but not in L1 inputs. LTD induced by 5-HT was blocked by the 5-HT₂ receptor antagonist ketanserin, an NMDA receptor antagonist and by intracellular Ca²⁺ chelation. The 5-HT₂ receptor agonist α-me-5-HT mimicked the LTD induced by 5-HT. However, the application of carbachol induced muscarinic receptor-dependent LTD in both inputs. The differential layer-specific induction of LTD by neuromodulators might play an important role in information processing mechanism of the prefrontal cortex.