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Williams HF, Layfield HJ, Vallance T, Patel K, Bicknell AB, Trim SA, Vaiyapuri S. The Urgent Need to Develop Novel Strategies for the Diagnosis and Treatment of Snakebites. Toxins (Basel) 2019; 11:E363. [PMID: 31226842 PMCID: PMC6628419 DOI: 10.3390/toxins11060363] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 06/18/2019] [Accepted: 06/18/2019] [Indexed: 01/09/2023] Open
Abstract
Snakebite envenoming (SBE) is a priority neglected tropical disease, which kills in excess of 100,000 people per year. Additionally, many millions of survivors also suffer through disabilities and long-term health consequences. The only treatment for SBE, antivenom, has a number of major associated problems, not least, adverse reactions and limited availability. This emphasises the necessity for urgent improvements to the management of this disease. Administration of antivenom is too frequently based on symptomatology, which results in wasting crucial time. The majority of SBE-affected regions rely on broad-spectrum polyvalent antivenoms that have a low content of case-specific efficacious immunoglobulins. Research into small molecular therapeutics such as varespladib/methyl-varespladib (PLA2 inhibitors) and batimastat/marimastat (metalloprotease inhibitors) suggest that such adjunctive treatments could be hugely beneficial to victims. Progress into toxin-specific monoclonal antibodies as well as alternative binding scaffolds such as aptamers hold much promise for future treatment strategies. SBE is not implicit during snakebite, due to venom metering. Thus, the delay between bite and symptom presentation is critical and when symptoms appear it may often already be too late to effectively treat SBE. The development of reliable diagnostical tools could therefore initiate a paradigm shift in the treatment of SBE. While the complete eradication of SBE is an impossibility, mitigation is in the pipeline, with new treatments and diagnostics rapidly emerging. Here we critically review the urgent necessity for the development of diagnostic tools and improved therapeutics to mitigate the deaths and disabilities caused by SBE.
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Affiliation(s)
| | | | - Thomas Vallance
- School of Pharmacy, University of Reading, Reading RG6 6AH, UK.
| | - Ketan Patel
- School of Biological Sciences, University of Reading, Reading RG6 6AH, UK.
| | - Andrew B Bicknell
- School of Biological Sciences, University of Reading, Reading RG6 6AH, UK.
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Chee KH, Amudha K, Hussain NA, Haizal HK, Choy AMJ, Lang CC. Combination of drugs acting on the natriuretic system and the renin-angiotensin system in heart failure. J Renin Angiotensin Aldosterone Syst 2016; 4:140-8. [PMID: 14608517 DOI: 10.3317/jraas.2003.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Conventional diuretic agents are very effective agents in relieving volume overload and congestive symptoms in chronic heart failure (CHF). However, they are associated with activation of the renin-angiotensin system (RAS) and the sympathetic nervous system and a reduction in glomerular filtration rate, all of which have been associated with adverse outcomes in CHF. Therefore, there is an increasing interest in drugs that target the natriuretic system without neurohormonal activation and deterioration of renal function. In this review, we will discuss the underlying rationale and evidence behind currently pursued strategies that target the natriuretic system. This includes the administration of natriuretic peptides (NPs) and strategies that potentiate the NP system, such as neutral endopeptidase inhibition. We will also highlight some potentially important interactions of these strategies with drugs that target the RAS.
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Affiliation(s)
- Kok H Chee
- Department of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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Petras D, Heiss P, Harrison RA, Süssmuth RD, Calvete JJ. Top-down venomics of the East African green mamba, Dendroaspis angusticeps, and the black mamba, Dendroaspis polylepis, highlight the complexity of their toxin arsenals. J Proteomics 2016; 146:148-64. [PMID: 27318176 DOI: 10.1016/j.jprot.2016.06.018] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2016] [Revised: 06/04/2016] [Accepted: 06/13/2016] [Indexed: 01/24/2023]
Abstract
We report the characterization, by combination of high-resolution on-line molecular mass and disulfide bond profiling and top-down MS/MS analysis, of the venom proteomes of two congeneric African snake species of medical importance, Dendroaspis angusticeps (green mamba) and D. polylepis (black mamba). Each of these mamba venoms comprised more than two-hundred polypeptides belonging to just a few toxin families. Both venom proteomes are overwhelmingly composed of post-synaptically-acting short- and long-chain neurotoxins that potently inhibit muscle- and neuronal-type nicotinic acetylcholine receptors; muscarinic cardiotoxins; and dendrotoxins, that block some of the Kv1, n-class of K+ channels. However, the identity of the major proteins and their relative abundances exhibit marked interspecific variation. In addition, the greater resolution of the top-down venomic analytical approach revealed previously undetected protein species, isoforms and proteoforms, including the identification and precise location of modified lysine residues in a number of proteins in both venoms, but particularly in green mamba toxins. This comparative top-down venomic analysis unveiled the untapped complexity of Dendroaspis venoms and lays the foundations for rationalizing the notably different potency of green and black mamba lethal arsenals at locus resolution. SIGNIFICANCE PARAGRAPH We report the characterization, by combination of high-resolution on-line molecular mass and disulfide bond profiling and top-down MS/MS analysis, of the venom proteomes of two congeneric African snake species of medical importance, Dendroaspis angusticeps (green mamba) and D. polylepis (black mamba). Each of these mamba venoms comprised more than two-hundred polypeptides belonging to just a few toxin families. Both venom proteomes are overwhelmingly composed of post-synaptically-acting short- and long-chain neurotoxins that potently inhibit muscle- and neuronal-type nicotinic acetylcholine receptors; muscarinic cardiotoxins; and dendrotoxins, that block some of the Kv1, n-class of K+ channels. However, the identity of the major proteins and their relative abundances exhibit marked interspecific variation. In addition, the greater resolution of the top-down venomic analytical approach revealed previously undetected protein species, isoforms and proteoforms, including the identification and precise location of modified lysine residues in a number of proteins in both venoms, but particularly in green mamba toxins. This comparative top-down venomic analysis unveiled the untapped complexity of Dendroaspis venoms and lays the foundations for rationalizing the notably different potency of green and black mamba lethal arsenals at locus resolution.
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Affiliation(s)
- Daniel Petras
- Technische Universität Berlin, Institut für Chemie, Berlin, Germany; University of California-San Diego, Skaggs School of Pharmacy & Pharmaceutical Sciences, La Jolla, CA, USA
| | - Paul Heiss
- Technische Universität Berlin, Institut für Chemie, Berlin, Germany
| | - Robert A Harrison
- Alistair Reid Venom Research Unit, Liverpool, School of Tropical Medicine, Liverpool, United Kingdom
| | | | - Juan J Calvete
- Instituto de Biomedicina de Valencia, CSIC, Valencia, Spain.
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Park SA, Kim TG, Han MK, Ha KC, Kim SZ, Kwak YG. Dendroaspis natriuretic peptide regulates the cardiac L-type Ca2+ channel activity by the phosphorylation of α1c proteins. Exp Mol Med 2012; 44:363-8. [PMID: 22366884 PMCID: PMC3389074 DOI: 10.3858/emm.2012.44.6.041] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Dendroaspis natriuretic peptide (DNP), a new member of the natriuretic peptide family, is structurally similar to atrial, brain, and C-type natriuretic peptides. However, the effects of DNP on the cardiac function are poorly defined. In the present study, we examined the effect of DNP on the cardiac L-type Ca2+ channels in rabbit ventricular myocytes. DNP inhibited the L-type Ca2+ current (ICa,L) in a concentration dependent manner with a IC50 of 25.5 nM, which was blocked by an inhibitor of protein kinase G (PKG), KT5823 (1 µM). DNP did not affect the voltage dependence of activation and inactivation of ICa,L. The α1c subunit of cardiac L-type Ca2+ channel proteins was phosphorylated by the treatment of DNP (1 µM), which was completely blocked by KT5823 (1 µM). Finally, DNP also caused the shortening of action potential duration in rabbit ventricular tissue by 22.3 ± 4.2% of the control (n = 6), which was completely blocked by KT5823 (1 µM). These results clearly indicate that DNP inhibits the L-type Ca2+ channel activity by phosphorylating the Ca2+ channel protein via PKG activation.
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Affiliation(s)
- Seon-Ah Park
- Department of Pharmacology, Chonbuk National University Medical School, Jeonju, Korea
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Kim SM, Kim YA, Kim SY, Kim SH, Cho KW, Kim SZ. Presence of dendroaspis natriuretic peptide and its binding to NPR-A receptor in rabbit kidney. ACTA ACUST UNITED AC 2010; 167:42-9. [PMID: 21130122 DOI: 10.1016/j.regpep.2010.11.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 11/10/2010] [Accepted: 11/25/2010] [Indexed: 11/26/2022]
Abstract
Natriuretic peptides help to maintain sodium and fluid volume homeostasis in a healthy cardio-renal environment. Since the identification of Dendroaspis natriuretic peptide (DNP) as a new member of the natriuretic peptide family, DNP has been considered as an important regulator of natriuresis and dieresis. The present study was undertaken to investigate the presence of immunoreactive Dendroaspis natriuretic peptide (DNP) and its specific receptor in rabbit. DNP was detected in heart, kidney, liver, brain, and plasma by radioimmunoassay (RIA). DNP contents of cardiac atrium and ventricle, renal cortex and medulla, liver, and brain were 1.42 ± 0.15, 1.0 6 ± 0.08, 2.55 ± 0.21, 1.81 ± 0.16, 1.36 ± 0.22, and 0.69 ± 0.15 pg/mg of wet weight, respectively. The concentration of DNP in plasma was 235.44 ± 15.44 pg/ml. By quantitative in vitro receptor autoradiography, specific ¹²⁵I-DNP binding sites were revealed in glomeruli, interlobular artery, acuate artery, vasa recta bundle, and inner medulla of the kidney with an apparent dissociation constant (K(d)) of 0.29 ± 0.05, 0.36 ± 0.03, 0.84 ± 0.19, 1.18 ± 0.23, and 10.91 ± 1.59 nM, respectively. Basal rate of 3', 5'-cyclic guanosine monophosphate (cGMP) production by particulate guanylyl cyclase (GC) activation of glomerular membranes was basally 13.40 ± 1.70 pmol/mg protein/min. DNP caused an increment of cGMP production in similar magnitude to that caused by ANP, BNP, and urodilatin, while the production of cGMP by CNP was significantly lower than that by DNP. Our results show that plasma levels of DNP were higher when compared to other tissues. DNP produces cGMP via the NPR-A receptor subtype in the kidney, similarly to ANP and BNP, suggesting that plasma DNP could have similar functions as ANP and BNP.
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Affiliation(s)
- Soo Mi Kim
- Department of Physiology, Institute for Medical Sciences, Center for Healthcare Technology Development, Chonbuk National University Medical School, Jeonju 561-180, Republic of Korea
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6
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Abstract
Since the discovery of atrial natriuretic factor by de Bold et al., there has been tremendous progress in our understanding of the physiologic, diagnostic and therapeutic roles of the natriuretic peptides (NPs) in health and disease. Natriuretic peptides are endogenous hormones that are released by the heart in response to myocardial stretch and overload. Three mammalian NPs have been identified and characterized, including atrial natriuretic peptide (ANP or atrial natriuretic factor), B-type natriuretic peptide (BNP), and C-type natriuretic peptide (CNP). In addition, Dendroaspis natriuretic peptide (DNP) has been isolated from the venom of Dendroaspis angusticeps (the green mamba snake), and urodilatin from human urine. These peptides are structurally similar and they consist of a 17-amino-acid core ring and a cysteine bridge. Both ANP and BNP bind to natriuretic peptide receptor A (NPR-A) that are expressed in the heart and other organs. Activation of NPR-A generates an increase in cyclic guanosine monophosphate, which mediates natriuresis, inhibition of renin and aldosterone, as well as vasorelaxant, anti-fibrotic, anti-hypertrophic, and lusitropic effects. The NP system thus serves as an important compensatory mechanism against neurohumoral activation in heart failure. This provides a strong rationale for the use of exogenous NPs in the management of acutely decompensated heart failure. In this article, the therapeutic applications of NPs in the acute heart failure syndromes are reviewed. Emerging therapeutic agents and areas for future research are discussed.
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Affiliation(s)
- Candace Y W Lee
- Cardiorenal Research Laboratory, Division of Cardiovascular Diseases, Department of Internal Medicine, Mayo Clinic College of Medicine, Rochester, MN 55906, USA.
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Johns DG, Ao Z, Heidrich BJ, Hunsberger GE, Graham T, Payne L, Elshourbagy N, Lu Q, Aiyar N, Douglas SA. Dendroaspis natriuretic peptide binds to the natriuretic peptide clearance receptor. Biochem Biophys Res Commun 2007; 358:145-9. [PMID: 17475216 DOI: 10.1016/j.bbrc.2007.04.079] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2007] [Accepted: 04/13/2007] [Indexed: 11/20/2022]
Abstract
Dendroaspis natriuretic peptide (DNP) is a newly-described natriuretic peptide which lowers blood pressure via vasodilation. The natriuretic peptide clearance receptor (NPR-C) removes natriuretic peptides from the circulation, but whether DNP interacts with human NPR-C directly is unknown. The purpose of this study was to test the hypothesis that DNP binds to NPR-C. ANP, BNP, CNP, and the NPR-C ligands AP-811 and cANP(4-23) displaced [(125)I]-ANP from NPR-C with pM-to-nM K(i) values. DNP displaced [(125)I]-ANP from NPR-C with nM potency, which represents the first direct demonstration of binding of DNP to human NPR-C. DNP showed high pM affinity for the GC-A receptor and no affinity for GC-B (K(i)>1000 nM). DNP was nearly 10-fold more potent than ANP at stimulating cGMP production in GC-A expressing cells. Blockade of NPR-C might represent a novel therapeutic approach in augmenting the known beneficial actions of DNP in cardiovascular diseases such as hypertension and heart failure.
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Affiliation(s)
- Douglas G Johns
- Vascular Biology and Thrombosis Department, Cardiovascular and Urogenital Center for Excellence in Drug Discovery, GlaxoSmithKline, King of Prussia, PA 19406, USA.
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8
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Singh G, Maguire JJ, Kuc RE, Skepper JN, Fidock M, Davenport AP. Characterization of the snake venom ligand [125I]-DNP binding to natriuretic peptide receptor-A in human artery and potent DNP mediated vasodilatation. Br J Pharmacol 2006; 149:838-44. [PMID: 17043672 PMCID: PMC2014690 DOI: 10.1038/sj.bjp.0706924] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND AND PURPOSE The natriuretic peptides, ANP and BNP, modulate vascular smooth muscle tone in human conduit arteries. Surprisingly, the natriuretic peptide receptor-A (NPR-A) has not been visualized using radioligand binding in these vessels. A new member of this peptide family, Dendroaspis natriuretic peptide (DNP) identified from snake venom, has been proposed to be present in human plasma and endothelial cells. Also, recently a novel radioligand, [(125)I]-DNP, has been characterized as selective for NPR-A in human heart. EXPERIMENTAL APPROACH Our aims were to investigate expression and function of NPR-A receptors in human mammary artery using [(125)I]-DNP to quantify receptor density, immunocytochemistry to delineate the cellular distribution of the receptor and in vitro pharmacology to compare DNP induced vasodilatation to that of ANP. KEY RESULTS Saturable, sub-nanomolar affinity [(125)I]-DNP binding was detected to smooth muscle of mammary artery, with receptor density of approximately 2 fmol mg(-1) protein, comparable to that of other vasoactive peptides. NPR-A immunoreactivity was localised to vascular smooth muscle cells and this was confirmed with fluorescence dual labelling. NPR-A expression was not detected in the endothelium. Like ANP, DNP fully reversed the constrictor response to ET-1 in endothelium intact or denuded mammary artery, with comparable nanomolar potencies. CONCLUSIONS AND IMPLICATIONS This is the first characterization of NPR-A in human mammary artery using [(125)I]-DNP and we provide evidence for the presence of receptor protein on vascular smooth muscle cells, but not endothelial cells. This implies that the observed vasodilatation is predominantly mediated via direct activation of smooth muscle NPR-A.
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MESH Headings
- Adrenomedullin/pharmacology
- Amino Acid Sequence
- Atrial Natriuretic Factor/pharmacology
- Calcitonin Gene-Related Peptide/pharmacology
- Dose-Response Relationship, Drug
- Elapid Venoms/metabolism
- Elapid Venoms/pharmacology
- Fluorescent Antibody Technique, Indirect
- Guanylate Cyclase/analysis
- Guanylate Cyclase/drug effects
- Guanylate Cyclase/metabolism
- Humans
- Immunohistochemistry
- In Vitro Techniques
- Intercellular Signaling Peptides and Proteins
- Ligands
- Mammary Arteries/chemistry
- Mammary Arteries/drug effects
- Mammary Arteries/metabolism
- Microscopy, Confocal
- Models, Biological
- Molecular Sequence Data
- Muscle, Smooth, Vascular/chemistry
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Peptides/metabolism
- Peptides/pharmacology
- Protein Binding
- Radiopharmaceuticals/metabolism
- Receptors, Atrial Natriuretic Factor/analysis
- Receptors, Atrial Natriuretic Factor/drug effects
- Receptors, Atrial Natriuretic Factor/metabolism
- Vasodilation/drug effects
- Vasodilator Agents/metabolism
- Vasodilator Agents/pharmacology
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Affiliation(s)
- G Singh
- Clinical Pharmacology Unit, University of Cambridge, Centre for Clinical Investigation, Addenbrooke's Hospital Cambridge, UK
| | - J J Maguire
- Clinical Pharmacology Unit, University of Cambridge, Centre for Clinical Investigation, Addenbrooke's Hospital Cambridge, UK
- Author for correspondence:
| | - R E Kuc
- Clinical Pharmacology Unit, University of Cambridge, Centre for Clinical Investigation, Addenbrooke's Hospital Cambridge, UK
| | - J N Skepper
- Department of Anatomy, Multi-Imaging Centre, University of Cambridge Cambridge, UK
| | - M Fidock
- Pfizer Global Research & Development Sandwich, Kent, UK
| | - A P Davenport
- Clinical Pharmacology Unit, University of Cambridge, Centre for Clinical Investigation, Addenbrooke's Hospital Cambridge, UK
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10
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Ha KC, Piao CS, Chae HJ, Kim HR, Chae SW. Dendroaspis natriuretic peptide protects the post-ischemic myocardial injury. ACTA ACUST UNITED AC 2005; 133:13-9. [PMID: 16289365 DOI: 10.1016/j.regpep.2005.09.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2005] [Accepted: 09/08/2005] [Indexed: 01/06/2023]
Abstract
The present study used isolated rat hearts to investigate whether (1) Dendroaspis natriuretic peptide (DNP) is protective against post-ischemic myocardial dysfunction, and (2) whether the cardioprotective effects of DNP is related to alteration of Bcl-2 family protein levels. The excised hearts of Sprague-Dawley rats were perfused on a Langendorff apparatus with Krebs-Henseleit solution with a gas mixture of 95% O2 and 5% CO2. Left ventricular end-diastolic pressure (LVEDP, mmHg), left ventricular developed pressure (LVDP, mmHg) and coronary flow (CF, ml/min) were continuously monitored. In the presence of 50 nM DNP, all hearts were perfused for a total of 100 min consisting of a 20 min pre-ischemic period followed by a 30 min global ischemia and 50 min reperfusion. Lactate dehydrogenase (LDH) activity in the effluent was measured during reperfusion. Treatment with DNP alone improved the pre-ischemic LVEDP and post-ischemic LVEDP significantly comparing with the untreated control hearts during reperfusion. However, DNP did not affect the LVDP, heart rate (HR, beats/min), and CF. Bcl-2, an anti-apoptotic protein expressed in ischemic myocardium of DNP+ischemia/reperfusion (I/R) group, was higher than that in I/R alone group. Bax, a pro-apoptotic protein expressed in ischemic myocardium of DNP+I/R group, has no significant difference compared with I/R alone group. These results suggest that the protective effects of DNP against I/R injury would be mediated, at least in part, through the increased ratio of Bcl-2 to Bax protein after ischemia-reperfusion.
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Affiliation(s)
- Ki-Chan Ha
- Department of Pharmacology and Institute of Cardiovascular Research, Chonbuk National University Medical School, Jeonju 561-182, Republic of Korea
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11
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Ha KC, Chae HJ, Piao CS, Kim SH, Kim HR, Chae SW. Dendroaspis natriuretic peptide induces the apoptosis of cardiac muscle cells. Immunopharmacol Immunotoxicol 2005; 27:33-51. [PMID: 15803858 DOI: 10.1081/iph-51292] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Early heart failure is characterized by elevated plasma Dendroaspis natriuretic peptide-like immunoreactivity (DNP-LI). However, the direct effects of DNP on heart or the heart-associated cell system are not well known. Therefore, we investigated whether DNP induces the apoptosis of H9c2 cardiac muscle cells. H9c2 cardiac muscle cells and rat neonatal cardiomyocytes were treated with various concentrations of DNP. Cell viability and nuclear morphology change were determined by trypan blue staining and Hoechst 33258 staining, respectively. Caspase-3-like activity was measured using specific fluorogenic substrates. Pro-and antiapoptotic proteins were assayed by Western blotting. DNP induced the apoptosis of H9c2 cardiac muscle cells in a dose-dependent manner. Maximum effects occurred at 100 nM concentration of DNP, with a 7-8-fold increase in apoptotic cells, to reach a maximum apoptotic index of 17%. We also identified that H9c2 cardiac muscle cells expressed Natriuretic peptide reactor -A and -B, which respond to DNP to generate cGMP. The treatment with DNP also markedly reduced levels of Bcl-2, inhibitor of apoptosis protein-1, and inhibitor of apoptosis protein-2 and increased the level of Bax and cytochrome c release into cytoplasm and subsequent caspase-3 activation, which co-occurred with increased apoptosis. DNP-induced apoptosis was mediated by cyclic GMP, and this effect was mimicked by dibutylyl-cGMP (30 microM), a membrane permeable analog of cGMP. Furthermore, DNP-induced apoptosis was observed in rat neonatal cardiomyocytes. These results suggest that DNP induces the apoptosis of H9c2 cardiac muscle cells and of cardiomyocytes via cGMP and demonstrate that the operative mechanism includes the regulation of Bcl-2 family proteins.
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Affiliation(s)
- Ki-Chan Ha
- Department of Pharmacology, Institute of Cardiovascular Research, Chonbuk National University Medical School, Chonju, Chonbuk, South Korea
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Fry BG, Wickramaratana JC, Lemme S, Beuve A, Garbers D, Hodgson WC, Alewood P. Novel natriuretic peptides from the venom of the inland taipan (Oxyuranus microlepidotus): isolation, chemical and biological characterisation. Biochem Biophys Res Commun 2005; 327:1011-5. [PMID: 15652496 DOI: 10.1016/j.bbrc.2004.11.171] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2004] [Indexed: 11/19/2022]
Abstract
Three natriuretic-like peptides (TNP-a, TNP-b, and TNP-c) were isolated from the venom of Oxyuranus microlepidotus (inland taipan) and were also present in the venoms of Oxyuranus scutellatus canni (New Guinea taipan) and Oxyuranus scutellatus scutellatus (coastal taipan). They were isolated by HPLC, characterised by mass spectrometry and Edman analysis, and consist of 35-39 amino acid residues. These molecules differ from ANP/BNP through replacement of invariant residues within the 17-membered ring structure and by inclusion of proline residues in the C-terminal tail. TNP-c was equipotent to ANP in specific GC-A assays or aortic ring assays whereas TNP-a and TNP-b were either inactive (GC-A over-expressing cells and endothelium-denuded aortic rings) or weakly active (endothelium-intact aortic rings). TNP-a and TNP-b were also unable to competitively inhibit the binding of TNP-c in endothelium-denuded aortae (GC-A) or endothelium-intact aortae (NPR-C). Thus, these naturally occurring isoforms provide a new platform for further investigation of structure-function relationships of natriuretic peptides.
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Affiliation(s)
- Bryan G Fry
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Qld 4072, Australia
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13
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Piao FL, Park SH, Han JH, Cao C, Kim SZ, Kim SH. Dendroaspis natriuretic peptide and its functions in pig ovarian granulosa cells. ACTA ACUST UNITED AC 2005; 118:193-8. [PMID: 15003836 DOI: 10.1016/j.regpep.2003.12.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2003] [Revised: 12/16/2003] [Accepted: 12/23/2003] [Indexed: 10/26/2022]
Abstract
Dendroaspis natriuretic peptide (DNP), a 38-amino acid peptide, was isolated from the venom of green mamba. It has structural and functional similarities to the other members of the natriuretic peptide family. The purpose of this study was to determine whether DNP is present in pig ovarian granulosa cells and to define its biological functions. The serial dilution curves of extracts of granulosa cells and follicular fluid were parallel to the standard curve of DNP, and a major peak of molecular profile of both extracts by HPLC was synthetic DNP. The concentration of DNP was 7.51+/-1.46 pg/10(7) cells and 24.81+/-2.38 pg/ml in granulosa cells and follicular fluid, respectively. Natriuretic peptides increased cGMP production in the purified membrane of granulosa cells with a rank order of potency of C-type natriuretic peptide (CNP)>atrial natriuretic peptide (ANP)=DNP. mRNAs for natriuretic peptide receptor-A (NPR-A), NPR-B and NPR-C were detected by RT-PCR. The binding site of (125)I-DNP was also observed in granulosa cell layer by in vitro autoradiography. Synthetic DNP inhibited the secretion of ANP from granulosa cells in a concentration-dependent manner and the potency was similar to CNP. The concentration of DNP and CNP, which inhibited the secretion of ANP by 50%, was about 1 nM. Increases in production of cGMP in granulosa cells were observed by DNP or CNP. Therefore, these results show the existence of DNP system and the cross-talk between natriuretic peptides in pig ovarian granulosa cells.
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Affiliation(s)
- Feng Lian Piao
- Department of Physiology, Medical School, Institute for Medical Sciences, Chonbuk National University, 2-20 Keum-Am-Dong-San, Jeonju 560-181, South Korea
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14
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Kim JH, Yang SH, Yu MY, Lee HK, Kim SY, Kim SH. Dendroaspis natriuretic peptide system and its paracrine function in rat colon. ACTA ACUST UNITED AC 2005; 120:93-8. [PMID: 15177925 DOI: 10.1016/j.regpep.2004.02.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2003] [Revised: 02/18/2004] [Accepted: 02/25/2004] [Indexed: 11/19/2022]
Abstract
Dendroaspis natriuretic peptide (DNP), a 38-amino-acid peptide, was isolated from the venom of Green Mamba. It has structural and functional similarities to other members of the natriuretic peptide family. The purpose of this study was to determine whether DNP system is present in the rat colon and to define its biological functions. The serial dilution curve of extracts of colonic tissues was parallel to the standard curve of DNP and a major peak of molecular profile by HPLC was synthetic DNP. The concentration of DNP was 0.5 +/- 0.04 ng/g of colonic tissues. DNP as well as atrial natriuretic peptide and C-type natriuretic peptide caused dose-dependent increases in cGMP production in the purified membrane of colonic tissues. Three types of natriuretic peptide receptor mRNAs were detected using semi-quantitative RT-PCR. Functionally, synthetic DNP inhibited the spontaneous contraction of rat colonic circular muscle in a concentration-dependent manner. The potency appeared to be at least 10 times greater than that of CNP. Furthermore, DNP inhibited carbachol-induced muscle contraction, suggesting that it also can modulate the nerve regulation of colonic motility. This study demonstrates the presence of DNP system in rat colon and its function as a local regulator of colonic motility.
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Affiliation(s)
- Jong Hun Kim
- Department of General Surgery, Chonbuk National University Medical School, Jeonju 560-181, South Korea
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15
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Campese VM, Nadim MK. Natriuretic Peptides. Hypertension 2005. [DOI: 10.1016/b978-0-7216-0258-5.50108-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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16
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Khurana VG, Wijdicks EFM, Heublein DM, McClelland RL, Meyer FB, Piepgras DG, Burnett JC. A Pilot Study of Dendroaspis Natriuretic Peptide in Aneurysmal Subarachnoid Hemorrhage. Neurosurgery 2004; 55:69-75; discussion 75-6. [PMID: 15214975 DOI: 10.1227/01.neu.0000126877.10254.4c] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2003] [Accepted: 02/13/2004] [Indexed: 11/19/2022] Open
Abstract
AbstractOBJECTIVE:Hypovolemia after aneurysmal subarachnoid hemorrhage (SAH) may be mediated by natriuretic peptides and can further impair cerebral perfusion in dysau-toregulated and vasospastic arterial territories. Dendroaspis natriuretic peptide (DNP), derived from the venom of Dendroaspis augusticeps, the Green Mamba snake, has recently been discovered in human plasma and atrial myocardium. There is no information regarding the presence or putative role of this peptide in patients with aneurysmal SAH.METHODS:A sensitive and specific DNP radioimmunoassay was performed on venous blood samples obtained on post-SAH Days 1, 3, and 7 from 10 consecutive SAH patients (cases) and randomly from 9 healthy volunteers (controls). Clinical and laboratory data, including daily serum sodium concentration and fluid balance, were collected prospectively up to 7 days after the ictus.RESULTS:Increase in plasma DNP levels occurred in five (63%) of eight patients who had DNP levels measured on Days 1 and 3 (mean increase, 29%). An increase in DNP level was significantly associated with development of a negative fluid balance (P = 0.003) and hyponatremia (P = 0.008). Three (75%) of the four patients who developed cerebral vasospasm during this study experienced an increase in DNP levels from Days 1 to 3.CONCLUSION:The present study is the first to find a significant association between elevated levels of DNP, a new member of the natriuretic peptide family, and the development of diuresis and natriuresis in patients with aneurysmal SAH. Our findings warrant further investigation by means of a large-scale, prospective, case-control study.
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Affiliation(s)
- Vini G Khurana
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota 55905, USA
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Pan S, Gulati R, Mueske CS, Witt TA, Lerman A, Burnett JC, Simari RD. Gene transfer of a novel vasoactive natriuretic peptide stimulates cGMP and lowers blood pressure in mice. Am J Physiol Heart Circ Physiol 2004; 286:H2213-8. [PMID: 14962842 DOI: 10.1152/ajpheart.00465.2003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Dendroaspis natriuretic peptide (DNP) is a recently described peptide produced by Dendroaspis angusticeps with structural and functional similarities to mammalian natriuretic peptides. These similarities suggest a potential role for DNP in cardiovascular therapeutics. To determine the physiological effects of chronic delivery of DNP, a gene transfer approach using first generation adenoviral vectors was utilized. Although the gene for DNP has not been cloned in any species, the peptide sequence in the snake is known. Preferred mammalian codons for snake DNP were cloned downstream of either the leader sequence (referred to as pBDNP-1) or prepropeptide sequence of human brain natriuretic peptide (BNP) cDNA (referred to as pBDNP-2). Transfections with pBDNP-1 or pBDNP-2 resulted in expected forms of chimeric DNP (cDNP) in cell lysates and conditioned media. Functional studies demonstrated the ability of both forms of cDNP within conditioned media to stimulate cGMP production in human vascular smooth muscle cells (hVSMC). Expressed cDNP inhibited hVSMC proliferation and stimulated vasorelaxation in a similar fashion. To investigate the chronic physiological effects of administration of cDNP, an adenoviral vector expressing cDNP (Ad-BDNP) was generated. Intravenous delivery of Ad-BDNP in mice resulted in dose-dependent systemic expression of cDNP. The highest level of expression was associated with consistent elevation of its presumed second messenger (cGMP) for 21 days but with transient lowering of systolic blood pressure in normotensive mice. This study demonstrates the biological features of the expression of the xenogenic peptide DNP.
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Affiliation(s)
- Shuchong Pan
- Division of Cardiovascular Diseases and Internal Medicine, College of Medicine, Mayo Clinic and Foundation, 200 First Street SW, Rochester, MN 55905, USA
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18
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Kim SW, Lee JU, Kim SZ, Choi KC, Kim NH, Cho KW. Enhanced Dendroaspis natriuretic peptide immunoreactivity in experimental ureteral obstruction. Nephron Clin Pract 2002; 92:369-72. [PMID: 12218316 DOI: 10.1159/000063302] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Whether the postobstructive diuresis can in part be related to an altered regulation of Dendroaspis natriuretic peptide (DNP) was investigated. Male Sprague-Dawley rats were bilaterally obstructed of their ureters. Control group was with sham ureteral obstruction. Forty-eight h later, tissue levels of DNP immunoreactivity were determined in the plasma, heart, and kidneys. Urine samples were collected in some rats under anesthesia. The plasma DNP immunoreactivity was significantly increased by 45% in the experimental group. The tissue levels of DNP immunoreactivity in the atrium, ventricle, or kidneys did not significantly differ between the experimental and control groups. The urinary flow and sodium excretion rate were 3- to 4-fold increased in the experimental group. The urinary DNP excretion was also increased in the experimental group, which was positively correlated with the urinary volume and sodium excretion. The urinary excretion of cGMP was 2- to 3-fold increased in the experimental group. These results indicate that an enhanced DNP activity may in part be causally related to the postobstructive diuresis.
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Affiliation(s)
- Soo Wan Kim
- Department of Physiology and Research Institute of Medical Sciences, Chonnam National University Medical School, 5 Hak-dong, Gwangju 501-746, Republic of Korea
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Lainchbury JG, Lisy O, Burnett JC, Meyer DM, Redfield MM. Actions of a novel synthetic natriuretic peptide on hemodynamics and ventricular function in the dog. Am J Physiol Regul Integr Comp Physiol 2002; 282:R993-8. [PMID: 11893602 DOI: 10.1152/ajpregu.00388.2001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Dendroaspis natriuretic peptide (DNP) is a recently discovered peptide with structural similarity to known natriuretic peptides. DNP has been shown to possess potent renal actions. Our objectives were to define the acute hemodynamic actions of DNP in normal anesthetized dogs and the acute effects of DNP on left ventricular (LV) function in conscious chronically instrumented dogs. In anesthetized dogs, DNP, but not placebo, decreased mean arterial pressure (141 +/- 6 to 109 +/- 7 mmHg, P < 0.05) and pulmonary capillary wedge pressure (5.8 +/- 0.3 to 3.4 +/- 0.2 mmHg, P < 0.05). Cardiac output decreased and systemic vascular resistance increased with DNP and placebo. DNP-like immunoreactivity and guanosine 3',5'-cyclic monophosphate concentration increased without changes in other natriuretic peptides. In conscious dogs, DNP decreased LV end-systolic pressure (120 +/- 7 to 102 +/- 6 mmHg, P < 0.05) and volume (32 +/- 6 to 28 +/- 6 ml, P < 0.05) and LV end-diastolic volume (38 +/- 5 to 31 +/- 4 ml, P < 0.05) but not arterial elastance. LV end-systolic elastance increased (6.1 +/- 0.7 to 7.4 +/- 0.6 mmHg/ml, P < 0.05), and Tau decreased (31 +/- 2 to 27 +/- 1 ms, P < 0.05). The effects on hemodynamics, LV function, and second messenger generation suggest synthetic DNP may have a role as a cardiac unloading and lusitropic peptide.
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Affiliation(s)
- John G Lainchbury
- Cardiorenal Research Laboratory, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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Affiliation(s)
- A Mark Richards
- Christchurch Cardioendocrine Research Group, Christchurch School of Medicine and Health Sciences, PO Box 4345, Christchurch, New Zealand.
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21
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Woodard GE, Rosado JA, Brown J. Dendroaspis natriuretic peptide-like immunoreactivity and its regulation in rat aortic vascular smooth muscle. Peptides 2002; 23:23-9. [PMID: 11814614 DOI: 10.1016/s0196-9781(01)00575-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Dendroaspis natriuretic peptide (DNP) is a recently isolated 38 amino acid peptide that shares structural and functional properties with the other members of the natriuretic peptide family. The present study demonstrates the presence of DNP-like immunoreactivity in sections of rat aorta, carotid artery and renal vasculature and tubules. DNP-like immunoreactivity was detected in culture aortic vascular smooth muscle cells and medium and is regulated by endothelin-1, angiotensin II and sodium nitroprusside but not by transforming growth factor-beta. Our observations indicate that DNP elicits a marked inhibitory effect on DNA synthesis in culture rat aortic vascular smooth muscle cells.
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Affiliation(s)
- Geoffrey E Woodard
- Department of Physiology, University of Cambridge, Downing Street, CB2 3EG, Cambridge, UK.
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Fábrega E, Crespo J, Rivero M, Casafont F, Castro B, García-Unzueta MT, Amado JA, Pons-Romero F. Dendroaspis natriuretic peptide in hepatic cirrhosis. Am J Gastroenterol 2001; 96:2724-9. [PMID: 11569702 DOI: 10.1111/j.1572-0241.2001.04131.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Dendroaspis natriuretic peptide (DNP) is a novel peptide that is structurally similar to atrial, brain, and C-type natriuretic peptides. Many natriuretic peptides are increased in hepatic cirrhosis, but the role of DNP in cirrhosis is unknown at present. The aim of the study was to investigate plasma levels of dendroaspis natriuretic-like immunoreactivity in cirrhosis. METHODS We measured plasma concentrations of DNP by radioimmunoassay methods in 12 cirrhotic patients without ascites and 44 cirrhotic patients with ascites, and compared these values with 20 age-matched healthy subjects. Renal function, plasma cGMP concentration, plasma renin activity, and plasma endothelin concentration were measured in each patient. RESULTS Patients without ascites had circulating levels of DNP similar to those of healthy subjects. By contrast, patients with ascites had increased circulating DNP levels compared to both patients without ascites and healthy subjects. In addition, circulating levels of DNP increased in relation to the severity of cirrhosis. Significant positive correlations were also found between DNP levels, endothelin concentrations, and plasma renin activity. CONCLUSIONS The results of this study indicate that plasma DNP is increased in cirrhotic patients with ascites.
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Affiliation(s)
- E Fábrega
- Gastroenterology and Hepatology Unit, University Hospital Marquis de Valdecilla, Santander, Spain
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Chai OH, Kim EK, Lee YH, Kim JG, Baik BJ, Lee MS, Han EH, Kim HT, Song CH. Histamine release induced by dendroaspis natriuretic peptide from rat mast cells. Peptides 2001; 22:1421-6. [PMID: 11514023 DOI: 10.1016/s0196-9781(01)00483-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Dendroaspis natriuretic peptide (DNP), recently isolated from the venom of the green Mamba snake Dendroaspis angusticeps, is a 38 amino acid peptide containing a 17 amino acid disulfide ring structure similar to that of the natriuretic peptide family. The natriuretic peptide family is known to induce histamine release from human and rat mast cells, but there are no published data concerning the effects of DNP on histamine release from mast cells. The purpose of this study is to investigate whether DNP induces the histamine release from rat peritoneal mast cells (RMPCs) and to determine the mechanism of DNP-induced histamine release from RPMCs. After treatment of RPMC with DNP, mast cell degranulation was observed, and calcium uptake and histamine release were measured. DNP released the histamine, induced the mast cell degranulation, and increased the calcium uptake of RPMCs, in a dose-dependent manner. The results indicate that DNP can increase Ca-uptake and induce histamine release.
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Affiliation(s)
- O H Chai
- Department of Anatomy, Chonbuk National University Medical School, 561-756, Chonju, South Korea
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Lisy O, Lainchbury JG, Leskinen H, Burnett JC. Therapeutic actions of a new synthetic vasoactive and natriuretic peptide, dendroaspis natriuretic peptide, in experimental severe congestive heart failure. Hypertension 2001; 37:1089-94. [PMID: 11304508 DOI: 10.1161/01.hyp.37.4.1089] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Dendroaspis natriuretic peptide (DNP), a recently discovered peptide, shares structural similarity to the other known natriuretic peptides, ANP, BNP, and CNP. Studies have reported that DNP is present in human and canine plasma and atrial myocardium and increased in plasma of humans with congestive heart failure (CHF). In addition, synthetic DNP is markedly natriuretic and diuretic and is a potent activator of cGMP in normal animals. To date, the ability of synthetic DNP to improve cardiorenal function in experimental CHF is unknown. Synthetic DNP was administered intravenously at 10 and 50 ng. kg(-1). min(-1) in dogs (n=7) with severe CHF induced by rapid ventricular pacing for 10 days at 245 bpm. In addition, we determined endogenous DNP in normal (n=4) and failing (n=4) canine atrial and ventricular myocardium. We report that administration of synthetic DNP in experimental severe CHF has beneficial cardiovascular, renal, and humoral properties. First, DNP in CHF decreased cardiac filling pressures, specifically right atrial pressure and pulmonary capillary wedge pressure. Second, DNP increased glomerular filtration rate in association with natriuresis and diuresis despite a reduction in mean arterial pressure. Third, DNP increased plasma and urinary cGMP and suppressed plasma renin activity. Fourth and finally, we report that DNP immunoreactivity is present in canine atrial and ventricular myocardium and increased in CHF. These studies report the acute intravenous actions of synthetic DNP in experimental severe CHF and suggest that on the basis of its beneficial properties, DNP may have potential as a new intravenous agent for the treatment of decompensated CHF.
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Affiliation(s)
- O Lisy
- Cardiorenal Research Laboratory, Division of Cardiovascular Diseases, Departments of Physiology and Internal Medicine, Mayo Clinic and Foundation, Rochester, MN 55905, USA.
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