• Title/Summary/Keyword: second messenger

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연수 신경세포 배양에서 세로토닌 분비에 대한 Cholecystokinin의 작용 (Effect of Cholecystokinin on Serotonin Release from Cultured Neurons of Fetal Rat Medulla Oblongata)

  • 송동근;조현미;이태희;서홍원;김영희
    • 대한약리학회지
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    • 제31권1호
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    • pp.11-15
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    • 1995
  • 연수의 세로토닌 신경계는 내재성 하행성 동통 억제계 (endogenous descending pain inhibitory system) 에 있어서 중추적인 역할을 하고 있다. 연수의 세로토닌 신경세포에 대한 cholecystokinin (CCK) 및 second messenger systems에 작용하는 약물들의 작용을 알아보기 위하여, 쥐의 태자 (태생 14일) 로부터 연수를 분리하여 10동안 배양한 후 5-hydroxytryptamine (5-HT)의 분비에 대한 cholecystokinin (CCK) 및 second messenger systems에 작용하는 약물의 영향을 연구하였다. 배양 10일된 세포에 여러 neuropeptide들을 $10{\mu}M$ 농도로 48 시간동안 자극한 결과, CCK 와 substance P에 의하여 5-HT의 분비가 증가됨을 관찰하였다. Somatostatin, proctolin, thyrotropin releasing hormone, 및 interleukin-6 은 5-HT의 분비에 있어서 아무런 영향이 없었다. 어떠한 second messenger가 CCK에 의한 5-HT 분비에 연관되어 있나를 알아보기 위하여 calcium channel 봉쇄제인 nimodipine, 그리고 calmodulin 길항제인 calmidazolium의 영향을 살펴본 결과 nimodipine ($1{\mu}M$)은 거의 완전하게, 그리고 calmidazolium ($1{\mu}M$)은 부분적으로 유의하게 CCK에 의한 5-HT의 분비를 억제하였다. 또한 adenyl cyclase의 활성도를 높이는 forskolin ($5{\mu}M$)은 5-HT의 분비를 증가시켰지만 protein kinase C(PKC)를 활성화시키는 phorbol myristate acetate (PMA)는 $2{\mu}M$ 농도에서 5-HT의 분비에 아무런 영향을 미치지 아니하였다. 이상의 연구결과, calcium channel을 통한 calcium influx와 세포내 calmodulin이 CCK에 의한 5-HT분비 증가에 있어서 중요한 역할을 함을 제시한다. 또한, 5-HT의 분비에 있어서 cyclic AMP system이 중요한 역할을 하나, PKC system은 5-HT의 분비에 연관이 없음을 제시하고 있다.

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Roles for the lipid-signaling enzyme MitoPLD in mitochondrial dynamics, piRNA biogenesis, and spermatogenesis

  • Gao, Qun;Frohman, Michael A.
    • BMB Reports
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    • 제45권1호
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    • pp.7-13
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    • 2012
  • Phospholipase D (PLD), a superfamily of signaling enzymes that most commonly generate the lipid second messenger Phosphatidic Acid (PA), is found in diverse organisms from bacteria to man and functions in multiple cellular pathways. A fascinating member of the family, MitoPLD, is anchored to the mitochondrial surface and has two reported roles. In the first role, MitoPLD-generated PA regulates mitochondrial shape through facilitating mitochondrial fusion. In the second role, MitoPLD performs a critical function in a pathway that creates a specialized form of RNAi required by developing spermatocytes to suppress transposon mobilization during meiosis. This spermatocyte-specific RNAi, known as piRNA, is generated in the nuage, an electron-dense accumulation of RNA templates and processing proteins that localize adjacent to mitochondria in a structure also called intermitochondrial cement. In this review, we summarize recent findings on these roles for MitoPLD functions, highlighting directions that need to be pursued to define the underlying mechanisms.

흰쥐 시상하부에서 신호전달계의 활성화에 의한 단백질 인산화의 변화 (Activation of Signal Transduction Pathways Changes Protein Phosphorylation Patterns in the Rat Hvpothalamus)

  • Lee, Byung-Ju;Sun
    • 한국동물학회지
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    • 제37권1호
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    • pp.130-136
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    • 1994
  • Although alteration in protein phosphorylation by specific protein kinases is of importance in transducing cellular signals in a variety of neural/endocrine systems, little is known about protein phosphorylation in the hvpothalamus. The present study aims to explore whether activation of the second messenger-dependent protein kinases affects phosphorylation of specific proteins using a cell free phosphorylation system followed by SDS-polvacrylamide gel electrophoresis. Cytoplasmic fractions derived from hvpothalami of immature rats were used as substrates and several activators and/or inhibitors of CAMP-, phosphatidylinositol- and Ca2+-calmodulin-dependent protein kinases were assessed. Many endogenous proteins were extensively phosphorylated and depending on the signal transduction pathways, phosphorvlation profiles were markedly different. The present data indicate that extracellular signals may affect cellular events through protein phosphorylation by second messengers-protein kinases in the rat hypothalamus.

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Hypertensive crisis following mRNA COVID-19 vaccination in adolescents: two case reports

  • Myung Hyun Cho;Hae Il Cheong
    • Childhood Kidney Diseases
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    • 제26권2호
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    • pp.97-100
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    • 2022
  • In response to the global coronavirus disease 2019 (COVID-19) pandemic, vaccines were developed and approved quickly. However, numerous cardiovascular adverse events have been reported. We present two adolescent cases who developed a hypertensive crisis following NT162b2 mRNA COVID-19 vaccination. Patient 1 was an 18-year-old male and his systolic blood pressure was 230 mmHg one day after the second vaccine. He was obese. No secondary cause of hypertension other than the vaccine was identified. Patient 2 was an 18-year-old male who complained with palpitation after the first vaccine. His blood pressure was 178/109 mmHg. He had autosomal dominant polycystic kidney disease. Both were treated with continuous infusion of labetalol followed by losartan, and blood pressure was controlled. Patient 2 received second vaccination and his blood pressure did not rise. It is warranted to measure blood pressure in adolescents at high risk of hypertension after NT162b2 mRNA COVID-19 vaccination.

$M_1$ Muscarine성 수용체에서 $^{123}Arginine$ 잔기의 Site-mutagenesis가 신호전달계에 미치는 영향 (Effects Of Site-mutagenesis of $^{123}Arginine$ residue in $M_1$ Muscarinic Receptor on the Signal Transduction System)

  • 이석용
    • 약학회지
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    • 제44권1호
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    • pp.52-59
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    • 2000
  • An exceptionally conserved sequence that is shared among most G protein-coupled neurotransmitter receptors is an aspartate-arginine-tyrosine triplet that is located at the second cytoplasmic domain. Using the ml subtype of muscarinic acetylcholine receptors as an example, a point mutation of the arginine residue at position 123 into asparagine was induced. This mutation resulted in a complete blockade of the carbachol-induced increases of PI hydrolysis and intracellular $Ca^2$$^{+}$ level, in spite of the expression of the wild-type and mutant receptors at similar concentrations in Chinese hamster ovary cells. In marked contrast, the muscarinic agonist carbachol induced concentration-dependent enhancement of the activity of NO synthase at mutant ml receptors although the enhancement was significantly smaller than at wild-type ml receptors. These data suggest that this highly conserved arginine residue plays an important role in coupling of muscarinic receptors to the second messenger systems and the presence of alternate mechanisms of activation of neuronal NO synthase which might be operative in the absence of large changes in the concentration of cellular $Ca^{2+}$.2+/.

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스마트폰 인스턴트 메신저를 이용한 개인적인 소통 활동이 직무성과에 미치는 영향 (The Effect of Personal Communication Activities using Smart Phone Instant Messenger on Job Performance)

  • 이종만
    • 인터넷정보학회논문지
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    • 제13권6호
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    • pp.17-24
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    • 2012
  • 본 연구는 직장인들이 정상근무시간 동안에 스마트폰 인스턴트 메신저를 개인적인 목적으로 이용하는 행동이 직무성과에 미치는 영향 정도를 파악하기 위하여 진행되었다. 이를 위해 스마트폰을 사용하는 직장인을 대상으로 설문조사를 실시하였고, 여기서 얻어진 데이터를 분석하기 위하여 구조방정식모델을 사용하였다. 구조방정식모델의 설계는 직장외부 지인 및 직장동료와의 인스턴트 메시징을 직무성과에 직접적인 영향을 미치는 요인으로 구성하였다. 또한 업무 특성은 직장 동료 및 직장 외부 지인과의 인스턴트 메시징과 직무성과간의 조절변수로 설정하였다. 분석결과는 첫째, 직장외부 지인과의 인스턴트 메시징 활동은 직무성과에 부정적인 영향을 미치며, 그 영향정도는 상호의존성이 높은 업무에 있어서 더 큰 것으로 판명되었다. 둘째, 직장동료와의 인스턴트 메시징 활동은 직무성과에 긍정적인 영향을 미치는 것으로 밝혀졌다.

RBL-2H3에서 IgE-dependent Histamine-releasing Factor에 의한 활성산소종 생성에 관한 연구 (Generation of ROS by IgE-Dependent Histamine-Releasing Factor in RBL-2H3 Cells)

  • 주이신;이경림
    • 한국미생물·생명공학회지
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    • 제33권3호
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    • pp.231-235
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    • 2005
  • RBL-2H3 cell에서 HRE에 의하여 histamine이 분비되는 과정에서 ROS가 생성되는지 실험해 본 결과, ROS가 HRF를 처리한지 5분대에 최대치를 보이며 생성되었다가 소멸되는 것을 관찰할 수 있었다. 따라서 HRF가 세포내 second messenger로써의 ROS를 생성하였다고 확인할 수 있었다. 또한 ROS는 단백질 정제 과정에서의 endotoxin오염에 의해 영향을 받지만,본 실험에서 규명한 HRF에 의한 ROS 생성은 endotoxin에 의한 것이 아닌, 순수하게 HRF에 의한 signaling의 결과라는 것도 확인할 수 있었다.

백서 재생간조직의 낙산탈수소효소 A-유전자 발현의 전사활성 (Transcriptional Control of Lactate Dehydrogenase A-Gene Expression during the Pre-replicative Phase of Regenerating Rat Liver)

  • 김해영;이승기
    • 약학회지
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    • 제32권4호
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    • pp.239-244
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    • 1988
  • Transcriptional rate of lactate dehydrogenase A-gene(LDH-A) during the prereplicative phase of regenerating rat liver was determined by in vitro run-off transcription assay. The results show that the transcription rate of LDH A-gene increases between 12 hours and 15 hours peaking at 13 hours after partial hepatectomy of rat liver. The increased rate of LDH A-gene transcription was interfered after DL-propranolol treatment intraperitoneally injected twice at 1 hour and 8 hours after partial hepatectomy indicating that the transcriptional control of LDH A-gene expression may be mediated by beta adrenergic receptor and cAMP as a second messenger. And also was it shown that the temporally increased rate of LDH A-gene transcription was maximum one hour after the second cAMP-surge which is known to play an important role for the initiation of DNA replication during regeneration of rat liver. And the transcriptional rate of LDH A-gene was decreased to the basal level at the time period when the hepatocytes proliferate rapidly suggesting that the induced LDH Aisozyme may be required for the initiation of DNA replication during regeneration of rat liver. These data may be supporting for the hypothesis suggesting that the induced LDH A-isozyme during the pre-replicative phase of regenerating rat liver may play bifunctional roles as a glycolytic enzyme and a helix destablizing protein as well.

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맛의 신호전달 (Taste Transduction)

  • 임호수
    • 한국식품영양과학회지
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    • 제32권4호
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    • pp.645-653
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    • 2003
  • Taste receptor cells respond to gustatory stimuli using a complex arrangement of receptor molecules, signaling cascades and ion channels. When stimulated, these cells produce action potentials that result in the release of neurotransmitter onto an afferent nerve fiber that in turn relays the identity and intensity of the gustatory stimuli to tie brain. A variety of mechanisms are used in transducing the four primary tastes. Direct interaction of the stimuli with ion channels appears to be of particular importance in transducing stimuli reported as salty or sour, whereas tile second messenger systems cyclic AMP and inositol trisphosphate are important in transducing bitter and sweet stimuli. In addition to the four basic tastes, specific mechanisms exist for the amino acid glutamate, which is sometimes termed the fifth primary taste. The emerging picture is that not only do individual taste qualities use more than one mechanism, but multiple pathways are available for individual tastants as well.

Regulation of $Ca^{2+}$ Signaling in Pulmonary Hypertension

  • Firth, Amy L.;Won, Jun Yeon;Park, Won Sun
    • The Korean Journal of Physiology and Pharmacology
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    • 제17권1호
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    • pp.1-8
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    • 2013
  • Understanding the cellular and molecular mechanisms involved in the development and progression of pulmonary hypertension (PH) remains imperative if we are to successfully improve the quality of life and life span of patients with the disease. A whole plethora of mechanisms are associated with the development and progression of PH. Such complexity makes it difficult to isolate one particular pathway to target clinically. Changes in intracellular free calcium concentration, the most common intracellular second messenger, can have significant impact in defining the pathogenic mechanisms leading to its development and persistence. Signaling pathways leading to the elevation of $[Ca^{2+}]_{cyt}$ contribute to pulmonary vasoconstriction, excessive proliferation of smooth muscle cells and ultimately pulmonary vascular remodeling. This current review serves to summarize the some of the most recent advances in the regulation of calcium during pulmonary hypertension.