• 제목/요약/키워드: $H_2$-receptor antagonist

검색결과 158건 처리시간 0.033초

흰쥐 해마에서 Acetylcholine 유리에 미치는 Adenosine 및 Magnesium의 영향 (Influence of Adenosine and Magnesium on Acetylcholine Release in the Rat Hippocampus)

  • 최봉규;윤영복
    • 대한약리학회지
    • /
    • 제29권2호
    • /
    • pp.175-182
    • /
    • 1993
  • 흰쥐 해마 (hippocampus)에서 acetylcholine(ACh) 유리에 미치는 adenosine 및 이에 미치는 magnesium의 역할에 관한 지견을 얻고자하여 $[^3H]-choline$으로 평형시킨 해마 slice를 사용하여 $[^3H]-ACh$ 유리에 미치는 여러가지 약물들의 영향을 관찰하였다. Adenosine $^*0.3{\sim}100{\mu}M$)은 전기자극 (3 Hz, $5\;Vcm^{-1}$, 2 ms, rectangular pulses)에 의한 $[^3H]-ACh$ 유리를 용량 의존적으로 감소시켰다. $A_1-adenosine$ 수용체 차단제인 8-cyclopentyl-1, 3-dipropylxanthine $(DPCPX,\;1-10\;{\mu}M)$은 용량 의존적으로 $[^3H]-ACh$ 유리를 증가시켰으며, adenosine과 $2{\mu}M$ DPCPX 동시 투여시 adenosine의 효과가 억제됨을 볼 수 있었다. $A_2$-수용체 흥분제인 5-(N-cyclopropyl)-carboxamidoadenosine $(CPCA,\;0.3{\sim}30\;{\mu}M)$은 자극에 의한 $[^3H]-ACh$ 유리를 용량 의존적으로 감소시켰으며, 이 역시 $2\;{\mu}M$ DPCPX 동시 투여시 그 효과가 차단됨을 관찰할 수 있었다. 그러나 또다른 $A_2$-흥분약인 CGS 21680C는 $[^3H]-ACh$ 유리에 별다른 영향을 미치지 못하였다. 한편 관류액내의 magnesium 농도를 변화시켰을때 magnesium 그 자체로는 $[^3H]-ACh$ 유리에 별다른 변화가 없었으며, magnesium을 4 mM로 증가시켰을때 adenosine의 효과가 크게 강화되어 용량 반응 곡선이 좌측으로 이동됨을 볼 수 있었다. 이상의 실험 결과로 adenosine은 흰쥐 해마의 choline 작동성 신경에 presynaptic $A_1-adenosine$ heteroreceptor를 통하여 ACh 유리 감소를 일으키며, 이러한 adenosine 작용은 magnesium이온에 의존적임을 알 수 있었다.

  • PDF

Mechanism of Relaxation of Rat Aorta by Scopoletin; an Active Constituent of Artemisia Capillaris

  • Kwon Eui Kwang;Jin Sang Sik;oChoi Min H;Hwang Kyung Taek;Shim Jin Chan;Hwang Il Taek;Han Jong Hyun
    • 동의생리병리학회지
    • /
    • 제16권2호
    • /
    • pp.389-396
    • /
    • 2002
  • In the present work, we examined the mechanism of vasorelaxant effect of scopoletin, an active constituent of Artemisia capillaris on rat thoracic descending aortic rings. Scopoletin induced a concentration-dependent relaxation in rat thoracic descending aortic rings pre-contracted with phenylephrine (EC/sub 50/ = 238.94±37.4 μM), while it was less effective in rat thoracic descending aortic rings precontracted with high potassium solution (KCI 30 mM). Vasorelaxation by scopoletin was significantly inhibited after endothelial removal, but recovered at high concentration. Pretreatment of rat thoracic descending aortic rings with N/sup G/-nitro-L-arginine (100 μM), a nitric oxide synthase inhibitor, and atropine (1 μM), a muscarinic receptor antagonist, significantly inhibited scopoletin-induced relaxation of rat thoracic descending aortic rings. Neither indomethacin (3 μM), an inhibitor of cydooxygenase, nor propranolol (1 μM), a β -adrenoceptor antagonist, modified the effect of scopoletin. The combination of N/sup G/ -nitro-L-arginine (100 μ M) and miconazole (10 μ M), an inhibitor of cytochrome P 450, did not modify the effect of scopoletin, when compared with pretreatment with N/sup G/-nitro-L-arginine(100 μM) alone. Vasorelaxant effect of scopoletin was inverted by pretreatment with diltiazem (10 μM), a Ca/sup 2+/-channel blocker, at low concentration, while restored at high concentration. Apamin (K/sub ca/-channel blocker, 1 μM), 4-aminopyridine (4-AP, K/sub v/-channel blocker, 1 mM), and tetrodotoxin (TTX, Na/sup +/-channel blocker 1 μM) potentiated the vasorelaxant effect of scopoledn, but glibendamide (K/sub ATP/-channel blocker, 10 μM), tetraetylammonium(TEA, non-selective K-channel blocker, 10 mM) did not affect the relaxation of scopoletin. Free radical scavengers (TEMPO, catalase, mannitol) did not modify vascular tone. These results suggest that nitric oxide, Ca/sup 2+/ -channels play a role in endothelium-dependent relaxations to scopoletin in rat aortas, that apamin, 4-AP, TTX but not glibenclamide, TEA potentiated relaxation to scopoletin mediated by these channels, and that free radicals do not concern to the vasorelaxant effect of scopoletin.

c-fos mRNA Expression in the Vestibular System following Hypergravity Stimulation in Rats

  • Jin Guang-Shi;Lee Jae-Hyo;Lee Jae-Hee;Lee Moon-Young;Kim Min-Sun;Jin Yuan Zhe;Song Jeong-Hoon;Park Byung-Rim
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제11권1호
    • /
    • pp.1-7
    • /
    • 2007
  • Altered environmental gravity, including both hypo- and hypergravity, may result in space adaptation syndrome. To explore the characteristics of this adaptive plasticity, the expression of immediate early gene c-fos mRNA in the vestibular related tissues following an exposure to hypergravity stimulus was determined in rats. The animals were subjected to a force of 2 g (twice earth's gravity) for 1, 3, or 12 h, and were examined poststimulus at 0, 2, 6, 12, and 24 h. RT-PCR (reverse transcription polymerase chain reaction) and real-time quantitative RT-PCR were adopted to analyze temporal changes in the expression of c-fos mRNA. The hypergravity stimulus increased the expression of c-fos mRNA in the vestibular ganglion, medial vestibular nucleus, inferior vestibular nucleus, hippocampus, cerebellum, and cortex. The peak expression occurred at 0 h poststimulation in animals stimulated with hypergravity for 1 h, and at 6 h poststimulus in those stimulated for 3 h. In contrast, those stimulated for 12 h exhibited dual peaks at 0 and 12 h poststimulus. Bilateral labyrinthectomy markedly attenuated the degree of c-fos mRNA expression. Glutamate receptor antagonist also dramatically attenuated the degree of c-fos mRNA expression. These results indicate that expression of c-fos mRNA in response to hypergravity occurs in the vestibular related tissues of the central nervous system, in which peripheral vestibular receptors and glutamate receptors play an important role. The temporal pattern of c-fos mRNA expression depended on the duration of the hypergravity stimulus.

In vitro Transport of Fexofenadine.HCl in Deformable Liposomes Across the Human Nasal Epithelial Cell Monolayers

  • Lin, Hong-Xia;Lee, Chi-Ho;Shim, Chang-Koo;Chung, Suk-Jae;Kim, Dae-Duk
    • Journal of Pharmaceutical Investigation
    • /
    • 제34권6호
    • /
    • pp.483-489
    • /
    • 2004
  • Fexofenadine HCl is non-sedating histamine H1 receptor antagonist that can be used for the treatment of seasonal allergic rhinitis. The objective of this study was to investigate whether the carriers of deformable liposomes can enhance the transepithelial permeability of fexofenadine HCl across the in vitro ALI human nasal monolayer model. Characterization of this model was achieved by bioelectric measurements and morphological studies. The passage 2 and 3 of cell monolayers exhibited the TEER value of $2852\;{\pm}\;482\;ohm\;{\times}\;cm^2$ on 11 days of seeding and maintained high TEER value for 5 days. The deformable liposome of fexofenadine HCl was prepared with phosphatidylcholine (PC) and cholic acid using extruder method. The mean particle size was about 200 nm and the maximum entrapment efficiency of 33.0% was obtained in the formulation of 1% PC and $100\;{\mu}g/ml$ fexofenadine HCl. The toxicity of the deformable liposome to human nasal monolayers was evaluated by MTT assay and TEER value change. MTT assay showed that it has no toxic effect on the nasal epithelial cells in 2-hour incubation when the PC concentration was below 1%. However, deformable liposome could not enhance the transepithelial permeability $(P_{app})$ and cellular uptake of fexofenadine HCl. In conclusion, the in vitro model could be used in nasal drug transport studies and evaluation of transepithelial permeability of formulations.

Effect of Calmodulin on Ginseng Saponin-Induced $Ca^{2+}$-Activated $Cl^{-}$ Channel Activation in Xenopus laevis Oocytes

  • Lee Jun-Ho;Jeong Sang-Min;Lee Byung-Hwan;Kim Jong-Hoon;Ko Sung-Ryong;Kim Seung-Hwan;Lee Sang-Mok;Nah Seung-Yeol
    • Archives of Pharmacal Research
    • /
    • 제28권4호
    • /
    • pp.413-420
    • /
    • 2005
  • We previously demonstrated the ability of ginseng saponins (active ingredients of Panax ginseng) to enhance $Ca^{2+}$-activated $Cl^{-}$ current. The mechanism for this ginseng saponin-induced enhancement was proposed to be the release of $Ca^{2+}$ from $IP_{3}-sensitive$ intracellular stores through the activation of PTX-insensitive $G\alpha_{q/11}$ proteins and PLC pathway. Recent studies have shown that calmodulin (CaM) regulates $IP_{3}$ receptor-mediated $Ca^{2+}$ release in both $Ca^{2+}-dependent$ and -independent manner. In the present study, we have investigated the effects of CaM on ginseng saponin-induced $Ca^{2+}$-activated $Cl^{-}$ current responses in Xenopus oocytes. Intraoocyte injection of CaM inhibited ginseng saponin-induced $Ca^{2+}$-activated $Cl^{-}$ current enhancement, whereas co-injection of calmidazolium, a CaM antagonist, with CaM blocked CaM action. The inhibitory effect of CaM on ginseng saponin-induced $Ca^{2+}$-activated $Cl^{-}$ current enhancement was dose- and time-dependent, with an $IC_{50} of 14.9\pm3.5 {\mu}M$. The inhibitory effect of CaM on saponin's activity was maximal after 6 h of intraoocyte injection of CaM, and after 48 h the activity of saponin recovered to control level. The half-recovery time was calculated to be $16.7\pm4.3 h$. Intraoocyte injection of CaM inhibited $Ca^{2+}$-induced $Ca^{2+}$-activated $Cl^{-}$ current enhancement and also attenuated $IP_{3}$-induced $Ca^{2+}$-activated $Cl^{-}$ current enhancement. $Ca^{2+}$/CaM kinase II inhibitor did not inhibit CaM-caused attenuation of ginseng saponin-induced $Ca^{2+}$-activated $Cl^{-}$ current enhancement. These results suggest that CaM regulates ginseng saponin effect on $Ca^{2+}$-activated $Cl^{-}$ current enhancement via $Ca^{2+}$-independent manner.

Cimentidine에 의(依)한 면역반응조절(免疫反應調節) (Modulation of Immune Response by Cimetidine)

  • 하대유;이헌구;송양근
    • 대한미생물학회지
    • /
    • 제16권1호
    • /
    • pp.49-55
    • /
    • 1981
  • 최근(最近) 히스타민이 면역반응(免疫反應)을 조절(調節)함이 구명(究明)되고 있으나 생체내(生體內) 실험(實驗) 특(特)히 마우스에서의 연구보고(硏究報告)를 희소(稀少)하다. 본(本) 실험(實驗)에서는 histamine-2-receptor antagonist($H_2$ 차단제(遮斷劑))인 cimetidine과 히스타민이 마우스의 면양적혈구(緬羊赤血球)(SRBC)에 대(對)한 면역반응(免疫反應)에 미치는 영향(影響)을 실험(實驗)하였다. 마우스를 매일(每日) 14일간(日間) 여러가지 농도(濃度)의 cimetidine 으로 전처리(前處理)하고 여러가지 농도(濃度)의 SRBC($10^6,\;10^7$$10^8$ 세포(細胞))로 면역(免疫)하고 4일(日) 후(後)에 마우스 족척(足蹠)에 SRBC로 야기주사(惹起注射)하여 Arthus반응(反應)과 지연성과민반응(遲延性過敏反應)(DTH)를 족척종창반응(足蹠腫脹反應)으로 측정(測定)하였으며, 체액성면역반응(體液性免疫反應)은 적혈구응집소가(赤血球凝集素價)를 측정(測定)하였다. 수(數) 종(種) 농도(濃度)($10^{-1}M,\;10^{-3}M$, 및 $10^{-5}M$)의 히스타민을 야기주사(惹起注射)와 동시(同時)에 주사(注射)하여 24시간(時間)-DTH를 측정(測定)하여 히스타민 효과(效果)를 평가(評價)하였다. Cimetidine은 DTH를 항진(亢進)시켰으며 그 항진(亢進)은 250 ${\mu}g$의 cimetidine을 투여(投與)하였을 때 현저(顯著)하였다. 그러나 Arthus 반응(反應)과 혈청항체가(血淸抗體價)는 cimetidine 전처리(前處理) 군(群)과 대조군간(對照群間)에 유의(有意)한 차이(差異)가 없었다. 히스타민은 SRBC에 대(對)한 DTH를 투여량-의존성(投與量-依存性) 유형(類型)으로 억제(抑側)하였으며 그 억제(抑制)는 저농도(低濃度)의 항원량(抗原量)($10^6$$10^7$ SRBC)일때 더 현저(顯著)하였다. 그러나 외인성(外因性) 히스타민은 $10^8$ SRBC로 면역(免疫)하였을 때늘 DTH를 감소(滅少)시키지 않았다. 이상(以上)의 본(本) 실험결과(實驗結果)는 cimetidine이 세포성(細胞性) 면역반응(免疫反應)을 항진(亢進)시키나 체액성(體液性) 면역반응(免疫反應)은 증가(增加)시키지 않으며 내인성(內因性) 및 외인성(外因性) 히스타민 즉시형과민반응(卽時型過敏反應)뿐만 아니라 세포성(細胞性) 면역반응(免疫反應) 조절(調節)에 관여(關與)함을 강력(强力)히 시사(示唆)하는 증거(證據)라고 사료(思料)되었다.

  • PDF

Paraquat에 의한 백서의 폐섬유화증에서 비선택적 Endothelin-1 receptor blocker($Bosentan^{(R)}$)의 치료효과 (The Effect of Nonspecific Endothelin-1 Receptor Blocker ($Bosentan^{(R)}$) on Paraquat Induced Pulmonary Fibrosis in Rat)

  • 정혜철;정기환;김병규;이승헌;김민경;김정열;박상면;이신형;신철;조재연;심재정;인광호;김한겸;유세화;강경호
    • Tuberculosis and Respiratory Diseases
    • /
    • 제50권2호
    • /
    • pp.182-195
    • /
    • 2001
  • 연구배경 : IPF에 의한 유병률과 사망률은 점차 증가하는 추세이나 좋은 치료는 없는 상태이다. 폐 섬유화 과정에서 TGF-${\beta}_1$, TNF-$\alpha$, ET-1, IFN-$\gamma$등의 사이토카인이 중요한 역할을 함이 알려져 있다. 본 실험은 파라콰트를 기관지 내로 주입하여 섬유화가 유발되는 과정의 백서의 폐 조직 내에서 ET-1과 TGF-${\beta}_1$의 발현을 살펴보고, 또한 비선택적 ET-1 receptor blocker인 Bosentan이 폐 섬유화의 치료에 효과가 있는지를 보고자 하였다. 방 법 : 웅성 7-8 주령의 백서 120 마리를 세 그룹으로 나누고 제 1그룹은 대조군으로 하여 기관지 내로 생리 식염수를 투여하였고, 제2그룹은 파라콰트를 투여하였으며, 제3그룹은 첫날 파라콰트를 투여한 후 매일 gastric gavage 방법으로 보센탄을 투여하였다. 파라콰트 혹은 생리식염수를 투여한 지 1, 3, 5, 7, 10, 14일째 각각 세 그룹의 일정 수를 희생하여 폐의 병리조직을 보고 면역세포화학염색으로 ET-1과 TGF-${\beta}_1$의 발현 율을 조사하여 분석하였다. 폐 섬유화의 정도는 H&E 염색과 Masson trichrome 염색을 하여 컴퓨터 영상분석을 시행하였고, 면역세포화학염색은 염색정도에 따라 반정량화하여 분석하였다. 결 과 : 파라콰트를 투여한 군이 대조군에 비해 콜라겐의 침착이 실험 3일째부터 현저히 증가하였고, ET-1과 TGF-${\beta}_1$의 발현이 주로 실험 초기에 증가하였다. 그러나 보센탄을 투여한 경우 콜라겐이 침착된 양에는 유의한 변화가 없었고 파라콰트군과 비교해서 ET-1과 TGF-${\beta}_1$의 발현에 뚜렷한 변화는 없었다. 결 론: 파라콰트를 투여한 경우 폐 섬유화가 증가하였다. 그리고 ET-1과 TGF-${\beta}_1$의 발현이 증가하였다. 그러나 ET-1 에 대한 receptor blocker인 보센탄이 폐 섬유화를 막지는 못하였다. 파라콰트에 의한 폐 섬유화에 ET-1이 연관성이 있으나 그 역할에 대해서는 추후 더 연구가 필요할 것으로 사료된다.

  • PDF

위식도 역류성 질환 관련 인후두성 역류(Laryngopharyngeal Reflux : LPR)증상을 호소하는 환자에서의 니자티딘의 치료효과 연구 (The Therapeutic Effects of Nizatidine in Gastroesophageal Disease with Laryngopharyngeal Reflux Symptoms: Observational Study)

  • 노영수;고중화;김광현;김명구;김병국;김성식;김영모;김영훈;김용복
    • 대한기관식도과학회지
    • /
    • 제9권1호
    • /
    • pp.67-74
    • /
    • 2003
  • Larygopharyngeal reflux(LPR) is one form of the Gastroesophageal Reflux Diseases(GERD). It is known to cause various kinds of otolaryngologic symptoms such as hoarseness, globus sensation in throat, chronic throat clearing, and chronic cough, Disease entities diagnosed by otolaryngologists as posterior laryngitis, globus pharyngeus and reflux laryngitis should be suspected as LPR-related diseases. The nizatidine(AXID), as a Histamine H2-receptor antagonist, reduces gastric acid secretion and improves gastric motility function. Objectives : The effect of nizatidine using 150mg b.i.d was evaluated for symptom relief and improvement of laryngoscopic findings in patients with LPR. Materials and Methods : In 30 multicenter, observational trial performed nationalwidely in Korea. 308 patients with LPR symptom were observed to evaluate their symptoms and larygnoscopic findings after 4weeks, 8weeks, 12weeks of treatment with nizatidine. Results : The symptoms of LPR including globus sensation, chronic throat clearing and hoarseness, are reduced significantly after 4 weeks, 8weeks, and 12weeks of treatment(p<0.05). The laryngoscopic findings including diffuse erythema, edema and granulation are improved after nizatidine treatment(p<0.05). and the efficacy of nizatidine on LPR-related sympoms after 4 weeks is 88.6%, and those of after 8 weeks and 12weeks were 92.6%, and 99.1% in ITT(Intent To Treatment) group(p<0.05). And PPA(Per Protocol Analysis)group showed 93.7%, 97.3%, and 99.1% of efficacy after 4, 8, and 12 weeks of nizatidine treatment(p<0.05). Conclusion : These results indicate that in patient with LPR, nizatidine 150mg b.i.d treatment very effectively reduces LPR symptoms and improves laryngoscopic findings as well as reduces gastric acid secretion and improves gastric motility function.

  • PDF

The Effect of Morphine on REST Expression in Human Neuroblastoma NMB Cells

  • Kim, Do-Kyung;Kim, Chun-Sung;Kim, Heung-Joong;Kook, Joong-Ki;Kim, Seung-Hee;Lee, Baek-Hee;Lee, Yun-Ho;Mo, Shin-Yeob;Loh, Horace H.
    • International Journal of Oral Biology
    • /
    • 제35권2호
    • /
    • pp.69-74
    • /
    • 2010
  • The mu opioid receptor (MOR) has been regarded as the main site of interaction with analgesics in major clinical use, particularly morphine. The repressor element-1 silencing transcription factor (REST) functions as a transcriptional repressor of neuronal genes in non-neuronal cells. However, it is expressed in certain mature neurons, suggesting that it may have complex and novel roles. In addition, the interactions between MOR and REST and their functions remain unclear. In this study, we examined the effects of morphine on the expression of REST mRNA and protein in human neuroblastoma NMB cells to investigate the roles of REST induced by MOR activation in neuronal cells. To determine the effects of morphine on REST expression, we performed RT-PCR, real-time quantitative RT-PCR, western blot analysis and radioligand binding assays in NMB cells. By RTPCR and real-time quantitative RT-PCR, the expression of REST was found to be unchanged by either the MOR agonist morphine or the MOR specific antagonist CTOP. By western blot, morphine was shown to significantly inhibit the expression of REST, but this suppression was completely blocked by treatment with CTOP. In the radioligand binding assay, the overexpression of REST led to an increased opioid ligand binding activity of endogenous MOR in the NMB cells. These results together suggest that morphine inhibits the expression of REST in human neuroblastoma cells through a post-transcriptional regulatory mechanism mediated through MOR.

Anxiolytic effect of Korean Red Ginseng through upregulation of serotonin and GABA transmission and BDNF expression in immobilized mice

  • Bui, Bich Phuong;Nguyen, Phuong Linh;Do, Ha Thi Thu;Cho, Jungsook
    • Journal of Ginseng Research
    • /
    • 제46권6호
    • /
    • pp.819-829
    • /
    • 2022
  • Background: Anxiolytic properties of Korean Red Ginseng (KRG) have been previously reported. However, the exact mechanism(s) of action remains to be elucidated. The present study investigated the effect of KRG on immobilization-induced anxiety-like behaviors in mice and explored the involvement of the serotonin and GABA systems and BDNF in the anxiolytic action. Methods: Mice were orally administered with KRG (200 mg/kg/day) for 4 weeks and immobilized once daily for 2 h. p-Chlorophenylalanine (p-CPA) was intraperitoneally injected on day 22-28, and flumazenil or bicuculline was injected on day 25-28. After behavioral evaluations, brains were dissected for biochemical analyses. Results: KRG improved immobilization-induced anxiety-like behaviors in mice, as assessed by the elevated plus maze (EPM) and marble burying tests (MBT). The anxiolytic effect of KRG was comparable to that of fluoxetine, a reference drug clinically used for anxiety disorders. A serotonin synthesis inhibitor, p-CPA, blocked the effect of KRG in the EPM and MBT, indicating the requirement of serotonin synthesis for anxiolytic action. In addition, the anxiolytic effect of KRG was inhibited by bicuculline (a GABAA antagonist) in MBT, implying the involvement of GABA transmission. Western blotting analyses revealed that KRG upregulated the expression of tryptophan hydroxylase and GABAA receptor in the brain, which was blocked by p-CPA. Enhanced BDNF expression by KRG in the hippocampus was also indicated to mediate the anxiolytic action of KRG in immobilized mice. Conclusion: KRG exhibited the anxiolytic effect in immobilized mice by multiple mechanisms of action, involving enhanced serotonin and GABA transmissions and BDNF expression.