• Title/Summary/Keyword: 신경작용제

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Agonist-Antagonist Effects of Buprenorphine on Action Potentials of Frog Sciatic Nerve Fibers (개구리 좌골신경에 대한 Buprenorphine의 작용 양상)

  • Lee, Jong-Hwa;Frank, George B.
    • The Korean Journal of Pharmacology
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    • v.25 no.1
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    • pp.23-30
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    • 1989
  • Buprenorphine, one of the mixed agonist-antagonist opioid drugs was used to inverstigate the opioid receptor on frog sciatic nerve A fibers. Action potentials were recorded for 4 hrs by a sucrose gap apparatus which were separated by four rubber membranes. To examine the one of the mechanism of action of buprenorphine, meperidine or naloxone was added after or before the treatment of buprenorphine. The results of this experiment were as follows: 1. Buprenorphine suppressed significantly the compound action potentials of frog sciatic nerve, and the maximal effects were shown both at $10^{-4}\;M$ and at $10^{-8}\;M$. 2. The dose-response relationship of buprenorphine on the depressant effect in frog sciatic nerve was biphasic and inverted U-shaped. 3. Buprenorphine blocked the effect of Meperidine $(10^{-3}\;M)$ on this preparation. 4. The depressant effcct of Buprenorphine on frog sciatic nerve was blocked by $10^{-8}\;M$ naloxone. From the above results, buprenorphine acts as one of agoinist-antagonistic effect on frog sciatic nerve, and the opioid receptor on this preparation is located on or near the intracellular opening of the sodium channels, which are sensitive to naloxone.

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저온 공기 표면 플라즈마 특성과 이를 이용한 화학작용제 제독

  • Jeong, Hui-Su;Seo, Jin-A;Choe, Seung-Gi
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.195.2-195.2
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    • 2016
  • 대기압 플라즈마는 공기중에서 방전이 가능하고, 이때 생성되는 활성산소종(ROS)과 활성질소종(RNS)을 적절히 이용하면 살균은 물론 제독이 가능하다. 특히 신경작용제나 수포작용제 등의 화학물질은 박테리아 포자, 세균, 바이러스 등의 생물작용제에 비해 더 많은 에너지와 시간이 요구된다. 현재 군이나 의료 시설에서는 과산화수소를 이용한 제독이나 염소계 표백제 성분으로 구성된 수용성 제독제를 이용하지만, 플라즈마의 경우는 단순히 기체를 방전하여 제독에 이용할 수 있으므로 보다 제독 시스템을 간단하게 구성할 수 있다. 하지만 대기압 방전시 방전전압을 낮추기 위해 헬륨과 알곤등의 기체를 공급하여 사용할 경우 부가적인 시스템의 규모가 커져 활용에 제한이 따른다. 따라서 본 연구에서는 대기중에 존재하는 질소, 산소 등을 이온화시키기 위해 10-25kHz의 주파수에서 4.5kV의 8us 펄스전원을 인가하여 공기 플라즈마를 얻고, 열에 의한 분해효과를 제거하기 위해 플라즈마의 기체온도를 20도로 유지시켰다. 플라즈마의 특성은 방출광 분석법을 이용하여 떨림온도를 계산하였고, 질소와 오존의 농도를 동시에 관찰하였다. 분해된 화학작용제는 기체분석기(Gas Chromatography)를 통해 표준 오염농도대비 잔류한 양을 측정함으로써 제독효율을 계산하였다.

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NMDA, quisqualate 및 kainate에 의하여 유발된 신경독성에 미치는 betaine의 효과

  • 박미정;김소라;김영중
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1994.04a
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    • pp.239-239
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    • 1994
  • 신경쇠약의 치료로 상용하며, 빈혈의 치료와 예방의 효과가 있으며, 노화방지에 도움이 되어 민간약으로는 장수(長壽)약으로 꼽히고 있는 구기자가 글루타메이트에 의한 신경독성을 차단하며, 이러한 효과는 구기자의 성분 중 betaine에 의하여 나타난다. Betaine이 어떠한 작용 기전에 의하여 글루타메이트에 의한 신경독성을 차단하는 지를 밝히기 위하여 글루타메이트가 작용하는 각기 다른 수용체인 NHDA 및 non-NMDA 수용체에 어떻게 작용하는 지를 알아보았다. 각 수용체의 선택적인 효능제인 NMDA, kainate 및 quisqualate 각각을 사용하여 인위적으로 독성을 유도시킨 후 이에 대한 betaine의 작용을 알아 본 결과 betaine은 quisqualate에 의하여 유도된 신경독성에서 모두 유사한 정도의 효과를 나타내었다. 이러한 효과는 betaine과 구조가 유사한 glycine의 다른 구조 유사체인 dimethylglycine이나 sarcosine과는 다른 작용양상을 나타내는 것이다. Dimethylglycine과 sarcosine은 kainate에 의한 독성에 대하여 미약한 효과를 나타냈으나, NMDA에 의한 독성에는 정상대조군의 LDH 값의 50% 이상에까지 이르게하는 효과를 나타내는 것으로 보아 이들이 NMDA에 의한 신경독성을 효과적으로 차단한다는 것을 암시해 준다고 할 수 있다. 그러나 betaine의 글루타메이트에 의한 신경독성을 차단하는 효과는 다른 glycine 구조 유사체처럼 glycine과 경쟁적으로 작용하여 나타나는 결과는 아니라고 여겨진다. 또한 글루타메이트에 의한 신경독성이 일어나는 기전 중의 하나가 calcium 이온의 세포내의 과도한 유입으로 인한 것으로 알려져 있으나 세포내의 calcium 이온의 양을 측정하여 본 결과 betaine은 글루타메이트로 인한 세포내 calcium 이온의 증가에 대하여 별다른 효과를 나타내지 않았다. 따라서 betaine의 글루타메이트에 의한 신경독성 차단 효과는 이미 미생물에서 보고된 바 있는 betaine의 세포내 삼투압에 대한 보호작용이나 항산화작용과 관련된 기전에 의하여 나타나는 것일 가능성이 높은 것으로 추측되어진다.

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Neuropeptides in Clinical Psychiatric Research : Endorphins and Cholecystokinins (정신질환에 있어서의 신경펩타이드 연구 - Endorphin과 cholecystokinin을 중심으로 -)

  • Kim, Young Hoon;Shim, Joo Chul
    • Korean Journal of Biological Psychiatry
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    • v.5 no.1
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    • pp.34-45
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    • 1998
  • We provide the reader with a brief introduction to the neurobiology of neuropeptides. Several comprehensive reviews of the distribution and neurochemical, neurophysiological, neuropharmacological and behavioral effects of the major neuropeptides have recently appeared. In reviews of the large number of neuropeptides in brain and their occurance in brain regions thought to be involved in the pathogenesis of major psychiatric disorders, investigators have sought to determine whether alternations in neuropeptide systems are associated with schizophrenia, mood disorders, anxiety disorders, alcoholism and neurodegenerative disease. There is no longer any doubt that neuropeptide-containing neurons are altered in several neuropsychiatric disorders. One of the factors that has hindered neuropeptide research to a considerable extent is the lack of pharmacological agents that specifically alter the synaptic availability of neuropeptides. With the exception of naloxone and naltrexone, the opiate-receptor antagonists, there are few available neuropeptide- receptor antagonists. Two independent classes of neuropeptide-receptor antagonists has been expected to be clinically useful. Naltrexone, a potent ${\mu}$-receptor antagonist, has been used successfully to reduce the need for alcohol consumption. And cholecycstokinin antagonists are now in development as a new class of anxiolytics, which would be expected to be free from tolerance and physical dependence and lack of sedation. In this review, we deal with these two kinds of neuropeptide system, the opioid system and cholesystokinins in the brain. The role of opioid systems in the reinforcement after alcohol consumtion and that of cholesystokinins in the pathogenesis of anxiety will be discussed briefly. As we know, the future for neuropeptides in psychiatry remains bright indeed.

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Investigation of the Pharmacological Mechanisms and the R&D of Medical Countermeasures Against Nerve Agent Poisoning (신경작용제 해독제의 약리기전 및 연구개발)

  • Cho, Young
    • Journal of the Korea Institute of Military Science and Technology
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    • v.14 no.5
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    • pp.920-931
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    • 2011
  • Nerve agents are irreversible inhibitors of the cholinesterase enzyme. Exposure causes a progression of toxic signs, including hypersecretions, fasciculations, tremor, convulsions, respiratory distress, epileptiform seizures, brain injuries and death. A combined regimen of prophylaxis and therapy is the most effective medical countermeasure for dealing with the threat of nerve agent poisoning to military personnel. In this paper, the author investigated the updated technologies regarding various pre- and post-treatment drugs for nerve agents detoxification which are under development in several countries including Korea. Some characteristics of active ingredients in the formulations of drugs, their action mechanisms, and effectiveness were analyzed. Additionally, part of experimental data on the transdermal patch studied in ADD using beagle dogs was introduced.

Norepinephrine과 Angiotensin II의 혈압상승작용에 대한 Diltiazem의 영향

  • 고석태;임동윤;유강준;최홍석;심기정
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1994.04a
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    • pp.298-298
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    • 1994
  • Norepinephrine이나 angotensin II가 그 작용을 나타내는데 $Ca^{+2}$의 세포내 유입 또는 유출과 밀접한 관련이 있다는 관점에서 $Ca^{+2}$ -channel차단제중 benzothiazenpine계인 diltiazem의 norepinephrine과 angiotensin II의 혈압상승작용에 대한 영향을 가토에서 관찰하였다. Norepinephrine과 angiotensin II의 혈압상승작용에 대한 diltiazem의 영향을 관찰하는 경우는 diltiazem을 투여한 일정시간후에 norepinephrine이나 angiotensin II을 투여하여 나타나는 혈압변화를 diltiazem투여전의 norepinephrine이나 angiotensin II의 혈압상승치와 비교 검토하였다. Diltiazem은 norepinephrine과 angiotensin II의 혈압상승작용을 억재하였으나 그 억제 시간은 지속적이지 않았다. 이와는 달리 diltiazem투여 30-40분에는 norepinephrine의 혈압상승작용의 강화현상이 나타났다. Diltiazem은 교감신경말단차단제인 bethanidine이나 신경절 차단제인 chlorisondamine 처리 가토에서도 norepinephrine이나 angiotensin II의 혈압상승작용을 억제하였다.

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A Case Study on the FDA Approval of Medical Treatments against Nerve Agent Poisoning (신경작용제 해독제 의약품 품목허가 사례 연구)

  • Lee, Keunwoo;An, Seoyeon;Hur, Byungil
    • Journal of the Korea Institute of Military Science and Technology
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    • v.19 no.1
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    • pp.119-126
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    • 2016
  • The US Army used MARK-1 composed of atropine autoinjector and 2-PAM autoinjector as a medical countermeasure against nerve agent poisoning. Recently, it has been being replaced by the ATNAA(Antidote Treatment Nerve Agent AutoInjector) for improvement the convenience in use and rapid detoxification effect. ATNAA(FDA approval, NDA 21-175, 2002. 1. 17) is a multi-chambered autoinjector that sequentially delivers atropine and 2-PAM through a single needle to allow Warfighters to survive against lethal exposure to nerve agents. In this paper, our group investigated the case of FDA approval of ATNAA in a point of the various data required by FDA guideline, thereby making it easy to meet the KFDA guideline for the approval of the prototype our group has been developed. The purpose of this study is to provide a reference for efficient research activities to minimize time and cost. Additionally, the purpose of this study is to provide a reference for the planning for the development of similar drug.

Molecular Mechanism of Action of Local Anesthetics: A Review

  • Yun, Il;Kang, Jung-Sook
    • Journal of Life Science
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    • v.2 no.2
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    • pp.97-107
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    • 1992
  • Strichartz and Richie have suggested that the mechanism of sodium donductance block of local anesthetics involves their interaction with a specific binding site within the sodium channel. However, there is evidence that local anesthetics can interact electrostatically with membrane proteins as well as membrane lipids. Whether or not all actions of local anesthetics are mediated by common site remains unclear. Thus, it can not be ruled out that local anesthetics concurrently interact with neuronal membrane lipids since sodium channels were found to be tightly associated with membrane lipids through covalent or noncovalent bonds. In summary, it is strongly postulated that local anesthetics, in addition to their direct interaction with sodium channels, concurrently interact with membrane lipids, fluidize the membrane, and thus induce conformational changes of sodium channels, which are known to be tightly associated with membrane lipids.

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NEW DRUG THERAPY IN CHILD AND ADOLESCENT PSYCHIATRY-NEW LONG-ACTING PSYCHOSTIMULANTS (소아청소년 정신과 영역에서의 새로운 약물치료:새로운 장기작용형 중추신경자극제)

  • Choi, Sung-Ku
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.14 no.1
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    • pp.3-11
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    • 2003
  • Attention-deficit/Hyperactivity disorder(ADHD) is the most common psychiatric disorder of childhood and among the most prevalent chronic health conditions affecting school-aged children. Children with ADHD experience significant functional problems, such as school difficulties, academic underachievement, troublesome interpersonal relationships with family members and peers, and low self-esteem. The most widely used pharmacological treatments for ADHD are psychostimulants, such as methylphenidate and amphetamine salts. These medications provide clinical efficacy by increasing the availability of catecholamines, primarily dopamine, in the frontal lobe of the brain. immediate-release(IR) formulations of sychostimulants were among the most effective psychotrophic medications in the psychopharmacological treatment. However, there are some limitations of IR formulations:the short half-life and duration of efficacy, which result in the need for multiple daily dosing and the poor compliance. These limitations have led to the development of once-daily, extended-release(ER) formulations of methylphenidate and amphetamine salts. However, these ER formulations may not be as immediately helpful to ADHD children due to delayed onset of action and the acute tolerance which is the failure to sustain the efficacy with the same concentration of drug as the initial stage of medication. OROS-methylphenidate(Concerta$^{\circledR}$) given once a day produces an ascending-pattern plasma drug level generated by the osmotically released, timed drug-delivery system. These new formulations of the psychostimulants have been shown to be a useful alternative to old stimulant medications through the evidence by the clinical trials.

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고추멀칭재배 - 잡초문제를 해결하려면$\cdots$

  • 양환승
    • The Bimonthly Magazine for Agrochemicals and Plant Protection
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    • v.10 no.1 s.88
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    • pp.55-61
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    • 1989
  • PE멀칭(피복) 재배시에 제초제를 사용하면 약제효과와 피복효과의 상승작용으로 잡초방제력이 월등히 높아진다. 주의할 것은, 파종상의 땅고르기와 흙부수기에 신경을 써야 제대로 효과를 얻을 수 있다.

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