51
|
Abstract
Although multiple advancements have been made in the treatment of heart failure (HF), mortality rates remain alarmingly high. The accepted arsenal of therapeutics includes a diuretic, digitalis, a beta-blocking agent and an inhibitor of the renin-angiotensin-aldosterone system. Despite the employment of a vast array of agents, nearly 300,000 patients in the US die annually with HF as a primary or contributory cause of death. Additional molecular targets are being evaluated in preclinical and clinical settings including vasopeptidase inhibitors, endothelin-1 receptor antagonists, arginine vasopressin antagonists, selective aldosterone blockers, TNF-alpha blockers and matrix metalloproteinase inhibitors. Although these approaches hold promise as viable therapeutics, a thorough evaluation of clinical benefit from these agents requires additional trials. Future disease-modifying approaches will also undoubtedly include cell transplantation and gene therapy. It is likely that notable advances in HF treatment will come from agents that attenuate myocardial remodelling. Indeed, maintenance or improvement of cardiac structure can attenuate HF development and improve mortality.
Collapse
Affiliation(s)
- Amy E Rudolph
- Cardiovascular & Metabolic Diseases, Pharmacia Corporation T1G, 800 North Lindbergh Blvd, St. Louis, Missouri 63167, USA
| | | |
Collapse
|
52
|
Abstract
Arginine vasopressin plays an important role in volume homeostasis. Patients with heart failure have chronically elevated plasma vasopressin concentrations which may contribute to their clinical syndrome of fluid retention. Recently, a number of agents have been developed to antagonize the effects of vasopressin by targeting its V1a and V2 receptors, which are involved in vascular tone and free water regulation, respectively. Two vasopressin antagonists, in particular, tolvaptan and conivaptan, have shown promise in animal studies and small-scale human trials. The following is a review of current experimental and clinical studies using vasopressin antagonists and their potential role in the treatment of heart failure.
Collapse
Affiliation(s)
- Pramod Sanghi
- Divison of Cardiology, Department of Internal Medicine, The University of Texas Medical Branch, School of Medicine, 5.106 John Sealy Annex, 301 University Blvd, Galveston, TX 77555-0553, USA
| | | | | |
Collapse
|
53
|
Kamath SA, Laskar SR, Yancy CW. Novel Therapies for Heart Failure: Vasopressin and Selective Aldosterone Antagonists. ACTA ACUST UNITED AC 2005; 11:21-9. [PMID: 15722667 DOI: 10.1111/j.1527-5299.2005.03912.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Despite favorable improvements in mortality, heart failure (HF) remains a problematic illness due to the ever-present burden of hospitalization. Clearly, novel treatment strategies are needed. This review focuses on two newer pharmacologic targets: arginine vasopressin and aldosterone. Arginine vasopressin receptor antagonists will most likely serve as an adjunct to or replacement of standard diuretic therapy in selected patients. The safety and efficacy of chronic therapy with oral arginine vasopressin receptor antagonists in large groups of congestive HF patients is currently under investigation. Aldosterone antagonism is emerging as a treatment of severe congestive HF. Recent large-scale clinical trials using aldosterone antagonists have proven that those with HF or left ventricular dysfunction postmyocardial infarction derive a survival benefit from aldosterone antagonism. Whether aldosterone antagonism should be prescribed in all patients with HF is unclear; however, in carefully selected and managed patients, aldosterone antagonism is helpful.
Collapse
Affiliation(s)
- Sandeep A Kamath
- Department of Internal Medicine/Cardiology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9047, USA
| | | | | |
Collapse
|
54
|
Saito T, Fukuzawa J, Osaki J, Sakuragi H, Yao N, Haneda T, Fujino T, Wakamiya N, Kikuchi K, Hasebe N. Roles of calcineurin and calcium/calmodulin-dependent protein kinase II in pressure overload-induced cardiac hypertrophy. J Mol Cell Cardiol 2003; 35:1153-60. [PMID: 12967638 DOI: 10.1016/s0022-2828(03)00234-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Calcineurin and calcium/calmodulin-dependent protein kinase (CaMK) II have been suggested to be the signaling molecules in cardiac hypertrophy. It was not known, however, whether these mechanisms are involved in cardiac hypertrophy induced by pressure overload without the influences of blood-derived humoral factors, such as angiotensin II. To elucidate the roles of calcineurin and CaMK II in this situation, we examined the effects of calcineurin and CaMK II inhibitors on pressure overload-induced expression of c-fos, an immediate-early gene, and protein synthesis using heart perfusion model. The hearts isolated from Sprague-Dawley rats were perfused according to the Langendorff technique, and then subjected to the acute pressure overload by raising the perfusion pressure. The activation of calcineurin was evaluated by its complex formation with calmodulin and by its R-II phosphopeptide dephosphorylation. CaMK II activation was evaluated by its autophosphorylation. Expression of c-fos mRNA and rates of protein synthesis were measured by northern blot analysis and by 14C-phenylalanine incorporation, respectively. Acute pressure overload significantly increased calcineurin activity, CaMK II activity, c-fos expression and protein synthesis. Cyclosporin A and FK506, the calcineurin inhibitors, significantly inhibited the increases in both c-fos expression and protein synthesis. KN62, a CaMK II inhibitor, also significantly prevented the increase in protein synthesis, whereas it failed to affect the expression of c-fos. These results suggest that both calcineurin and CaMK II pathways are critical in the pressure overload-induced acceleration of protein synthesis, and that transcription of c-fos gene is regulated by calcineurin pathway but not by CaMK II pathway.
Collapse
Affiliation(s)
- Tetsuya Saito
- First Department of Medicine, Asahikawa Medical College, 2-1-1-1 Midorigaoka-Higashi, Asahikawa 078 8510, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
55
|
Lee CR, Watkins ML, Patterson JH, Gattis W, O'connor CM, Gheorghiade M, Adams KF. Vasopressin: a new target for the treatment of heart failure. Am Heart J 2003; 146:9-18. [PMID: 12851603 DOI: 10.1016/s0002-8703(02)94708-3] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Arginine vasopressin is a peptide hormone that modulates a number of processes implicated in the pathogenesis of heart failure. Numerous vasopressin antagonists are currently under development for the treatment of this syndrome. METHODS Preclinical and clinical data describing the effects of vasopressin and the vasopressin antagonists on both normal physiology and heart failure were reviewed. RESULTS Through activation of V(1a) and V(2) receptors, vasopressin regulates various physiological processes including body fluid regulation, vascular tone regulation, and cardiovascular contractility. Vasopressin synthesis is significantly and chronically elevated in patients with heart failure despite the volume overload and reductions in plasma osmolality often observed in these patients. Vasopressin also appears to adversely effect hemodynamics and cardiac remodeling, while potentiating the effects of norepinephrine and angiotensin II. The selective V(2) and dual V(1a)/V(2) receptor antagonists tolvaptan and conivaptan, respectively, substantially increase free water excretion and plasma osmolality, reduce body weight, improve symptoms of congestion, and moderately increase serum sodium concentrations in patients with heart failure who present with symptoms of fluid overload. Tolvaptan effectively normalizes serum sodium concentrations in hyponatremic heart failure patients. Conivaptan significantly reduces pulmonary capillary wedge pressure without affecting systemic vascular resistance or cardiac output. The clinical significance of V(1a) receptor antagonism requires further investigation. CONCLUSIONS Current preclinical and clinical findings with the vasopressin antagonists appear promising, however further evaluation in phase III clinical trials is necessary to define the role of vasopressin antagonism in the treatment of heart failure.
Collapse
Affiliation(s)
- Craig R Lee
- School of Pharmacy, University of North Carolina at Chapel Hill, 27599-7075, USA
| | | | | | | | | | | | | |
Collapse
|
56
|
Yang XD, Zhao LY, Zheng QS, Li X. Effects of arginine vasopressin on growth of rat cardiac fibroblasts: role of V1 receptor. J Cardiovasc Pharmacol 2003; 42:132-5. [PMID: 12827038 DOI: 10.1097/00005344-200307000-00020] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The abnormal proliferation of cardiac fibroblasts is involved in the pathophysiologic process of left ventricular hypertrophy (LHV) associated with essential hypertension. Arginine vasopressin (AVP) has been reported to contribute significantly to the pathogenesis of hypertension. In this study, the authors investigated the effects of AVP and its V1 receptor antagonist [d(CH2)5Tyr2(Me)]AVP on the growth of rat cardiac fibroblasts. Cardiac fibroblasts of neonatal Sprague-Dawley rats were isolated, and growth-arrested cardiac fibroblasts were stimulated with 2.5% fetal calf serum in the presence and absence of AVP (0.001, 0.01, 0.1, and 1 microM) and [d(CH2)5Tyr2(Me)]AVP (0.1 microM). DNA synthesis was measured by [3H]thymidine incorporation. Thiazolyl blue assay and flow cytometry techniques were adopted to measure cell numbers and analyze cell cycle, respectively. Arginine vasopressin (0.1 and 1 microM) significantly increased DNA synthesis in cardiac fibroblasts. Moreover, AVP (0.1 and 1 microM) significantly increased the number of cardiac fibroblasts. Analysis of cell cycle showed that AVP (0.1 microM) increased S-stage percentage and proliferation index (PI). The V1 receptor antagonist [d(CH2)5Tyr2(Me)]AVP (0.1 microM) significantly inhibited DNA synthesis in cardiac fibroblasts. The cell number, S-stage percentage, and PI induced by AVP (0.1 microM) were significantly decreased by [d(CH2)5Tyr2(Me)]AVP (0.1 microM). These findings suggest that AVP might promote the proliferation of rat cardiac fibroblasts, which seems to be mediated via the V1 receptor. Arginine vasopressin may be involved in the pathophysiologic process of LVH by promoting cardiac fibroblast proliferation.
Collapse
Affiliation(s)
- Xue-Dong Yang
- Department of Cardiology, Tangdu Hospital, Fourth Military Medical University, ShaanXi Province, China
| | | | | | | |
Collapse
|
57
|
Holmes CL, Landry DW, Granton JT. Science Review: Vasopressin and the cardiovascular system part 2 - clinical physiology. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2003; 8:15-23. [PMID: 14975041 PMCID: PMC420051 DOI: 10.1186/cc2338] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Vasopressin is emerging as a rational therapy for vasodilatory shock states. In part 1 of the review we discussed the structure and function of the various vasopressin receptors. In part 2 we discuss vascular smooth muscle contraction pathways with an emphasis on the effects of vasopressin on ATP-sensitive K+ channels, nitric oxide pathways, and interaction with adrenergic agents. We explore the complex and contradictory studies of vasopressin on cardiac inotropy and coronary vascular tone. Finally, we summarize the clinical studies of vasopressin in shock states, which to date have been relatively small and have focused on physiologic outcomes. Because of potential adverse effects of vasopressin, clinical use of vasopressin in vasodilatory shock should await a randomized controlled trial of the effect of vasopressin's effect on outcomes such as organ failure and mortality.
Collapse
Affiliation(s)
- Cheryl L Holmes
- Staff intensivist, Department of Medicine, Division of Critical Care, Kelowna General Hospital, Kelowna BC, Canada
| | - Donald W Landry
- Associate Professor, Department of Medicine, Columbia University, New York, New York, USA
| | - John T Granton
- Assistant Professor of Medicine, Faculty of Medicine, and Program Director, Critical Care Medicine, University of Toronto, and Consultant in Pulmonary and Critical Care Medicine, Director Pulmonary Hypertension Program, University Health Network, Toronto, Ontario, Canada
| |
Collapse
|
58
|
|
59
|
Krum H, Liew D. New developments in the pharmacological treatment of chronic heart failure. Expert Opin Investig Drugs 2003; 12:751-7. [PMID: 12720487 DOI: 10.1517/13543784.12.5.751] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In recent years, rapid growth in the understanding of the pathophysiology of chronic heart failure has allowed for insights into many potential new therapeutic strategies. Yet until now, despite sound biological basis for efficacy and success in early-Phase studies, novel agents have not stood up to the scrutiny of late-Phase clinical trials. Indeed, remarkably negative results have been observed for vasopeptidase inhibitors, endothelin receptor antagonists and agents which block immune activation. However, efficacy data from other novel agents are still awaited, including the selective aldosterone receptor antagonist eplerenone, arginine vasopressin inhibitors, erythropoietin and hydroxy-methyl-glutaryl coenzyme A reductase inhibitors. Other classes of drugs which may enter clinical development include cardiac metabolic agents, matrix metalloproteinase inhibitors and advanced glycation end product antagonists. That the mortality and morbidity of patients with chronic heart failure remain unacceptably high makes the ongoing commitment to exploration of new drug therapies for the condition critical.
Collapse
Affiliation(s)
- Henry Krum
- Department of Medicine, Monash University Central and Eastern Clinical School, Alfred Hospital, Melbourne, Victoria 3004, Australia.
| | | |
Collapse
|
60
|
De Smet HR, Menadue MF, Oliver JR, Phillips PA. Endothelin ETA receptor antagonism does not attenuate angiotensin II-induced cardiac hypertrophy in vivo in rats. Clin Exp Pharmacol Physiol 2003; 30:278-83. [PMID: 12680847 DOI: 10.1046/j.1440-1681.2003.03831.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. Angiotensin (Ang) II causes cardiac hypertrophy in vitro and in vivo. It also stimulates the release of endothelin (ET)-1. Endothelin-1 induces hypertrophy of cardiomyocytes in vitro. 2. In the present study, we examined whether the cardiac hypertrophic action of AngII in vivo was mediated by ET-1 via ETA receptors. We also determined whether arginine vasopressin (AVP), another ET-1 stimulator, could cause cardiac hypertrophy in vivo through an ET-1-dependent pathway. 3. In Sprague-Dawley rats (n = 8 per group), we determined whether the orally administered ETA receptor antagonist BMS 193884 could attenuate the cardiac hypertrophic effect of: (i) i.v. AngII infusion at either 100 or 200 ng/kg per min, i.v., for 1 week; (ii) AngII infusion at 100 ng/kg per min, i.v., for 2 weeks; and (iii) AVP infusion at either 2 or 10 ng/kg per min, i.v., for 1 week. Mean arterial pressure and heart rate were also measured. 4. Infusion with AngII for both 1 and 2 weeks increased left ventricular weight. Only AngII infusion at 200 ng/kg per min for 1 week increased blood pressure. Endothelin ETA receptor blockade did not attenuate the left ventricular hypertrophy, even though it reduced the hypertensive effect of AngII. Arginine vasopressin increased blood pressure, but did not cause cardiac hypertrophy. 5. We showed that AngII can cause cardiac hypertrophy through a direct, blood pressure-independent effect on the heart. Endothelin-1 did not mediate the cardiac hypertrophic effect of AngII through ETA receptors. This may indicate the involvement of ETB receptors in this model of cardiac hypertrophy. Arginine vasopressin did not cause cardiac hypertrophy in vivo.
Collapse
Affiliation(s)
- H R De Smet
- Department of Medicine, Flinders University of South Australia, Bedford Park, Australia
| | | | | | | |
Collapse
|
61
|
Masetti P, Murphy SF, Kouchoukos NT. Vasopressin therapy for vasoplegic syndrome following cardiopulmonary bypass. J Card Surg 2002; 17:485-9. [PMID: 12643457 DOI: 10.1046/j.1540-8191.2002.01002.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Hypotension refractory to maximal doses of alpha-adrenergic drugs after cardiac operations employing cardiopulmonary bypass (CPB) has been referred as "vasoplegic syndrome." Vasopressin has been used for its therapy with encouraging results. MATERIAL AND METHODS 16 patients (mean age 71, range 47 to 84 years) were treated with intravenous vasopressin (0.1-1 IU/min) for hypotension refractory to maximal doses (>30 microg/kg/min) of norepinephrine after undergoing complex cardiac operations employing CPB. Preoperative ejection fraction was 40.5% (mean, range 20% to 60%), preoperative NYHA class was 3.5 (mean). Hemodynamic measurements were obtained one hour before and one hour after beginning vasopressin infusion; urine output was measured for the 4 hours before and the 4 hours after beginning the infusion. Duration of vasopressin treatment was 58.8 +/- 37.3 hours (mean +/- SD). RESULTS Systolic blood pressure increased from 89.6 +/- 7.9 to 119.6 +/- 10.5 mmHg (mean +/- SD) (p < 0.001); systemic vascular resistance increased from 688.0 +/- 261.7 to 1043.3 +/- 337.1 dyne/s/cm2 (mean +/- SD) (p < 0.001); cardiac index decreased from 2.69 +/- 0.8 to 2.2 +/- 0.5 L/min/m2 (mean +/- SD) (p < 0.008); urine output increased from 36.8 +/- 30.4 to 72.8 +/- 38.2 mL/h (mean +/- SD) (p < 0.001). Seven patients (44%) survived the hospital stay. CONCLUSIONS High-dose vasopressin is effective in the treatment of the vasoplegic syndrome after cardiac operations employing cardiopulmonary bypass.
Collapse
Affiliation(s)
- Paolo Masetti
- Division of Cardiovascular and Thoracic Surgery and the Heart Center, Missouri Baptist Medical Center, St. Louis, Missouri, USA
| | | | | |
Collapse
|
62
|
Van Kerckhoven R, Lankhuizen I, van Veghel R, Saxena PR, Schoemaker RG. Chronic vasopressin V(1A) but not V(2) receptor antagonism prevents heart failure in chronically infarcted rats. Eur J Pharmacol 2002; 449:135-41. [PMID: 12163117 DOI: 10.1016/s0014-2999(02)01972-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Evidence is increasing that therapeutic modulation of neurohormonal activation with vasopressin receptor antagonists via V(1A) and V(2) receptors may favourably affect prognosis of heart failure. This study was designed to compare in vivo hemodynamic effects of early treatment (1-21 days after infarction) with a V(1A) (SR-49059 or ((2S)1-[(2R3S)-5-chloro-3-(2-chlorophenyl)-1-(3,4-dimethoxybenzene-sulfonyl)-3-hydroxy-2,3-dihydro-1H-indole-2-carbonyl]-pyrrolidine-2-carboxamide); 0.3 mg/kg/day) and a V(2) (SR-121463B or (1-[4-(N-tert-Butylcarbamoyl)-2-methoxybenzene sulfonyl]-5-ethoxy-3-spiro-[4-(2-morpholinoethyoxy)-cyclo-hexane]indol-2one,furmate; 0.5 mg/kg/day) receptor antagonist in myocardial infarcted rats, chronically instrumented for hemodynamic measurements. Left ventricular dysfunction in conscious myocardial infarcted rats, which was evidenced by a significantly decreased cardiac output (myocardial infarction: 70+/-3 vs. sham: 81 +/- 3 ml/min) and stroke volume (myocardial infarction: 190 +/- 10 vs. sham: 221 +/- 7 microl), was restored by the vasopressin V(1A) (81+/-2 ml and 224 +/- 5 microl, respectively) but not V(2) receptor antagonist. Improved cardiac output with the vasopressin V(1A) receptor antagonist resulted from an increased stroke volume at a reduced myocardial infarction induced tachycardia. In addition to the hemodynamic measurements, left ventricular hypertrophy and capillary density were determined, histologically measured as the cross-sectional area of Gomori-stained myocytes and Lectin-stained capillaries per tissue area, respectively. The observed left ventricular concentric hypertrophy (myocardial infarction: 525 +/- 38 vs. sham: 347 +/- 28 microm(2); P < 0.05) and reduced capillary density (myocardial infarction: 2068 +/- 162 vs. sham: 2800 +/- 250 number/mm(2); P<0.05) in the spared myocardium of myocardial infarcted rats, remained unaffected by the vasopressin V(1A) or V(2) receptor antagonist. Thus, chronic vasopressin V(1A) but not V(2) receptor blockade prevents heart failure in 3-week-old infarcted rats. Moreover, the improved cardiac function could not attributed to changes in left ventricular hypertrophy and/or capillary density.
Collapse
Affiliation(s)
- Roeland Van Kerckhoven
- Department of Pharmacology, Faculty of Medicine and Health Sciences, Erasmus University Rotterdam, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands. ,eur.nl
| | | | | | | | | |
Collapse
|
63
|
Udelson JE, Smith WB, Hendrix GH, Painchaud CA, Ghazzi M, Thomas I, Ghali JK, Selaru P, Chanoine F, Pressler ML, Konstam MA. Acute hemodynamic effects of conivaptan, a dual V(1A) and V(2) vasopressin receptor antagonist, in patients with advanced heart failure. Circulation 2001; 104:2417-23. [PMID: 11705818 DOI: 10.1161/hc4501.099313] [Citation(s) in RCA: 239] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Arginine vasopressin may contribute to abnormalities in hemodynamics and fluid balance in heart failure through its actions on V(1A) (vascular and myocardial effects) and V(2) receptors (renal effects). Inhibiting the action of vasopressin may be beneficial in patients with heart failure. METHODS AND RESULTS A total of 142 patients with symptomatic heart failure (New York Heart Association class III and IV) were randomized to double-blind, short-term treatment with conivaptan, a dual V(1a)/V(2) vasopressin receptor antagonist, at a single intravenous dose (10, 20, or 40 mg) or placebo. Compared with placebo, conivaptan at 20 and 40 mg significantly reduced pulmonary capillary wedge pressure (-2.6+/-0.7, -5.4+/-0.7, and -4.6+/-0.7 mm Hg for placebo and 20 and 40 mg groups, respectively; P<0.05) and right atrial pressure (-2.0+/-0.4, -3.7+/-0.4, and -3.5+/-0.4 mm Hg for placebo and 20 and 40 mg groups, respectively; P<0.05) during the 3- to 6-hour interval after intravenous administration. Conivaptan significantly increased urine output in a dose-dependent manner (-11+/-17, 68+/-17, 152+/-19, and 176+/-18 mL/hour for placebo and 10, 20, and 40 mg groups, respectively; P<0.001) during the first 4 hours after the dose. Changes in cardiac index, systemic and pulmonary vascular resistance, blood pressure, and heart rate did not significantly differ from placebo. CONCLUSIONS In patients with advanced heart failure, vasopressin receptor antagonism with conivaptan resulted in favorable changes in hemodynamics and urine output without affecting blood pressure or heart rate. These data suggest that vasopressin is functionally significant in advanced heart failure and that further investigations are warranted to examine the effects of conivaptan on symptom relief and natural history in such patients.
Collapse
Affiliation(s)
- J E Udelson
- Division of Cardiology, New England Medical Center Hospitals/Tufts University School of Medicine, Boston, Massachusetts, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
64
|
Brostrom MA, Mourad F, Brostrom CO. Regulated expression of GRP78 during vasopressin-induced hypertrophy of heart-derived myocytes. J Cell Biochem 2001; 83:204-17. [PMID: 11573238 DOI: 10.1002/jcb.1219] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Although the development of cellular hypertrophy is widely believed to involve Ca(2+) signaling, potential supporting roles for sequestered Ca(2+) in this process have not been explored. H9c2 cardiomyocytes respond to arginine vasopressin with an initial mobilization of Ca(2+) stores and reduced rates of mRNA translation followed by repletion of Ca(2+) stores, up-regulation of translation beyond initial rates, and the development of hypertrophy. Rates of synthesis of the endoplasmic reticulum (ER) chaperones, GRP78 and GRP94, were found to increase preferentially at early times of vasopressin treatment. Total GRP78 content increased 2- to 3-fold within 8 h after which the chaperone was subject to post-translational modification. Preferential synthesis of GRP78 and the increase in chaperone content both occurred at pM vasopressin concentrations and were abolished at supraphysiologic Ca(2+) concentrations. Co-treatment with phorbol myristate acetate decreased vasopressin-dependent Ca(2+) mobilization and slowed appearance of new GRP78 molecules in response to the hormone, whereas 24 h pretreatment with phorbol ester prolonged vasopressin-dependent Ca(2+) mobilization and further increased rates of GRP78 synthesis in response to the hormone. Findings did not support a role for newly synthesized GRP78 in translational up-regulation by vasopressin. However up-regulation, which does not depend on Ca(2+) sequestration, appeared to expedite chaperone expression. This report provides the first evidence that a Ca(2+)-mobilizing hormone at physiologic concentrations signals increased expression of GRP78. Translational tolerance to depletion of ER Ca(2+) stores, typifying a robust ER stress response, did not accompany vasopressin-induced hypertrophy.
Collapse
Affiliation(s)
- M A Brostrom
- Department of Pharmacology, U.M.D.N.J.-Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA.
| | | | | |
Collapse
|
65
|
Brostrom MA, Reilly BA, Wilson FJ, Brostrom CO. Vasopressin-induced hypertrophy in H9c2 heart-derived myocytes. Int J Biochem Cell Biol 2000; 32:993-1006. [PMID: 11084379 DOI: 10.1016/s1357-2725(00)00037-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Protein synthesis in H9c2 heart-derived myocytes responds biphasically to arginine vasopressin (1 microM). An initial 50% inhibition attributable to Ca(2+) mobilization from the sarcoplasmic/endoplasmic reticulum is followed by a recovery that subsequently converts to a 1.5-fold stimulation. This study was undertaken to ascertain whether vasopressin programs H9c2 cells to undergo hypertrophy or to proliferate and whether early translational inhibition is required for programming. Translational suppression was observed only at vasopressin concentrations (>1 nM) causing extensive (>50%) depletion of Ca(2+) stores and was diminished at supraphysiologic extracellular Ca(2+) concentrations. Stimulation of protein synthesis, by contrast, was unaffected by changes in extracellular Ca(2+), depended on gene transcription, was suppressed by a protein kinase C pseudosubstrate sequence (peptide 19-27), and was observed at pM vasopressin concentrations. Activation of MAP kinases, phosphoinositide 3-kinase, calcineurin, S6 kinase, or eIF4 could not be implicated in the stimulation, which persisted for 24 h. Vasopressin-treated H9c2 cells underwent hypertrophy by standard criteria. Cellular protein accumulation occurred at pM hormone concentrations, was blocked by peptide 19-27, was observed regardless of retinoic acid pretreatment to prevent myogenic transdifferentiation, and preceded full repletion of Ca(2+) stores. It is proposed that H9c2 cells, which possess all basic features of V1-vasopressin receptor signaling, provide a convenient model for investigating vasopressin-induced myocyte hypertrophy. Early translational suppression is not needed for vasopressin-induced H9c2 myocyte hypertrophy whereas activation of protein kinase C appears essential.
Collapse
Affiliation(s)
- M A Brostrom
- Department of Pharmacology, UMDNJ-Robert Wood Johnson Medical School, 675 Hoes Lane, Piscataway, NJ 08854, USA.
| | | | | | | |
Collapse
|