• Title/Summary/Keyword: Guanylate cyclase

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Ginsenoside Re inhibits pacemaker potentials via adenosine triphosphate-sensitive potassium channels and the cyclic guanosine monophosphate/nitric oxide-dependent pathway in cultured interstitial cells of Cajal from mouse small intestine

  • Hong, Noo Ri;Park, Hyun Soo;Ahn, Tae Seok;Kim, Hyun Jung;Ha, Ki-Tae;Kim, Byung Joo
    • Journal of Ginseng Research
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    • v.39 no.4
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    • pp.314-321
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    • 2015
  • Background: Ginseng belongs to the genus Panax. Its main active ingredients are the ginsenosides. Interstitial cells of Cajal (ICCs) are the pacemaker cells of the gastrointestinal (GI) tract. To understand the effects of ginsenoside Re (GRe) on GI motility, the authors investigated its effects on the pacemaker activity of ICCs of the murine small intestine. Methods: Interstitial cells of Cajal were dissociated from mouse small intestines by enzymatic digestion. The whole-cell patch clamp configuration was used to record pacemaker potentials in cultured ICCs. Changes in cyclic guanosine monophosphate (cGMP) content induced by GRe were investigated. Results: Ginsenoside Re ($20-40{\mu}M$) decreased the amplitude and frequency of ICC pacemaker activity in a concentration-dependent manner. This action was blocked by guanosine 50-[${\beta}-thio$]diphosphate [a guanosine-5'-triphosphate (GTP)-binding protein inhibitor] and by glibenclamide [an adenosine triphosphate (ATP)-sensitive $K^{+}$ channel blocker]. To study the GRe-induced signaling pathway in ICCs, the effects of 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (a guanylate cyclase inhibitor) and RP-8-CPT-cGMPS (a protein kinase G inhibitor) were examined. Both inhibitors blocked the inhibitory effect of GRe on ICC pacemaker activity. L-NG-nitroarginine methyl ester ($100{\mu}M$), which is a nonselective nitric oxide synthase (NOS) inhibitor, blocked the effects of GRe on ICC pacemaker activity and GRe-stimulated cGMP production in ICCs. Conclusion: In cultured murine ICCs, GRe inhibits the pacemaker activity of ICCs via the ATP-sensitive potassium ($K^{+}$) channel and the cGMP/NO-dependent pathway. Ginsenoside Re may be a basis for developing novel spasmolytic agents to prevent or alleviate GI motility dysfunction.

Pharmacological Actions of New Woohwangchungsimwon Pill on Cardiovascular System (신우황청심원의 심혈관계에 대한 약효)

  • Cho, Tai-Soon;Lee, Sun-Mee;Kim, Nak-Doo;Huh, In-Hoi;Ann, Hyung-Soo;Kwon, Kwang-Il;Park, Seok-Ki;Shim, Sang-Ho;Shin, Dae-Hee;Park, Dai-Kyu
    • YAKHAK HOEJI
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    • v.41 no.6
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    • pp.802-816
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    • 1997
  • In order to investigate the pharmacological properties of New Woohwangehungsimwon Pill (NWCH). Effects of Woohwangehungsimwon Pill (WCH) and NWCH were compared using various experimental models. In isolated rat aorta, NWCH and WCH showed the relaxation of blood vessels in maximum contractile response to phenylephrine ($10^{-6}$M) without regard to endothelium containing or denuded rings of the rat aorta. Furthermore, the presence of the inhibitors of NO synthase and guanylate cyclase did not affect significantly the relaxative effects of NWCH and WCH. NWCH and WCH inhibited the vascular contractions induced by acethylcholine, prostaglandin endoperoxide or peroxide in a dose-dependent manner. In conscious spontaneously hypertensive rats(SHRs), NWCH and WCH decreased significantly heart rate. These, at high doses, had a negative inotropic effect that was a decrease of LVDP and (-dp/dt)/(+dp/dt) in the isolated perfused rat hearts, and also decreased the contractile force and heart rate in the isolated rat right atria. In excised guinea-pig papillary muscle, these had no effects on parameters of action potential at low doses, whereas inhibited the cardiac, contractility at high doses. Furthermore, these had a significant inhibitory effects on heart acceleration in normotensive rats and SHRs. These results suggested that NWCH and WCH have weak cardiovascular effects, and that there is no significant differences between two preparations.

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Identification and validation of putative biomarkers by in silico analysis, mRNA expression and oxidative stress indicators for negative energy balance in buffaloes during transition period

  • Savleen Kour;Neelesh Sharma;Praveen Kumar Guttula;Mukesh Kumar Gupta;Marcos Veiga dos Santos;Goran Bacic;Nino Macesic;Anand Kumar Pathak;Young-Ok Son
    • Animal Bioscience
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    • v.37 no.3
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    • pp.522-535
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    • 2024
  • Objective: Transition period is considered from 3 weeks prepartum to 3 weeks postpartum, characterized with dramatic events (endocrine, metabolic, and physiological) leading to occurrence of production diseases (negative energy balance/ketosis, milk fever etc). The objectives of our study were to analyze the periodic concentration of serum beta-hydroxy butyric acid (BHBA), glucose and oxidative markers along with identification, and validation of the putative markers of negative energy balance in buffaloes using in-silico and quantitative real time-polymerase chain reaction (qRT-PCR) assay. Methods: Out of 20 potential markers of ketosis identified by in-silico analysis, two were selected and analyzed by qRT-PCR technique (upregulated; acetyl serotonin o-methyl transferase like and down regulated; guanylate cyclase activator 1B). Additional two sets of genes (carnitine palmotyl transferase A; upregulated and Insulin growth factor; downregulated) that have a role of hepatic fatty acid oxidation to maintain energy demands via gluconeogenesis were also validated. Extracted cDNA (complementary deoxyribonucleic acid) from the blood of the buffaloes were used for validation of selected genes via qRTPCR. Concentrations of BHBA, glucose and oxidative stress markers were identified with their respective optimized protocols. Results: The analysis of qRT-PCR gave similar trends as shown by in-silico analysis throughout the transition period. Significant changes (p<0.05) in the levels of BHBA, glucose and oxidative stress markers throughout this period were observed. This study provides validation from in-silico and qRT-PCR assays for potential markers to be used for earliest diagnosis of negative energy balance in buffaloes. Conclusion: Apart from conventional diagnostic methods, this study improves the understanding of putative biomarkers at the molecular level which helps to unfold their role in normal immune function, fat synthesis/metabolism and oxidative stress pathways. Therefore, provides an opportunity to discover more accurate and sensitive diagnostic aids.

Serum Nitric Oxide and Tumor Necrosis Factor-α Levels in Patients with Kawasaki Disease (가와사키병 환아에서 면역글로불린 투여 전후의 혈중 Nitric Oxide와 Tumor Necrosis Factor-α에 대한 연구)

  • Park, Ji Hye;Shin, Jee Seon;Hong, Young Mi
    • Clinical and Experimental Pediatrics
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    • v.48 no.7
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    • pp.772-778
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    • 2005
  • Purpose : Kawasaki disease(KD) is a systemic panvasculitis that causes coronary artery lesions. KD is accompanied by immunoregulatory abnormalities. Nitric oxide(NO) can induce relaxation of blood vessels by activating guanylate cyclase in smooth muscle cells and high levels of NO may result in coronary artery lesions. We investigated tumor necrosis factor$(TNF)-{\alpha}$ and NO production before and after intravenous immunoglobulin(IVIG) therapy to study the roles of NO and $TNF-{\alpha}$ in KD with coronary artery lesions. Methods : Serum levels of NO and $TNF-{\alpha}$ were measured in 24 patients with KD(group I, eight patients with normal coronary artery; group II, 16 patients with coronary artery lesions) and 23 controls(group III, 13 afebrile controls; group IV, 10 febrile controls). Blood samples from each subject were drawn before and after IVIG therapy and in the convalescent stage. Serum concentrations of NO and $TNF-{\alpha}$ were measured by enzyme linked immuno sorbent assay. Results : The NO levels before IVIG therapy were significantly higher in group II than in group I, group III and group IV. After IVIG therapy the levels of NO were significantly higher in group I and group II than in group III. The $TNF-{\alpha}$ levels before IVIG therapy were significantly higher in group I and group II than in group III. The serum $TNF-{\alpha}$ and NO levels were higher before IVIG therapy and decreased through the convalescent stage in KD patients. In the acute stage of KD patients with coronary artery lesions, serum NO levels significantly correlated with white blood cells (r=0.43, P<0.05). Conclusion : The serum concentration levels of $TNF-{\alpha}$ and NO were abnormally high in KD patients and NO concentrations were statistically higher in the KD patients with coronary artery abnormalities than those without coronary abnormality during the early stage of the KD. These results suggest NO may be involved in the development of coronary artery lesions.