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LaPenna KB, Li Z, Doiron JE, Sharp TE, Xia H, Moles K, Koul K, Wang JS, Polhemus DJ, Goodchild TT, Patel RB, Shah SJ, Lefer DJ. Combination Sodium Nitrite and Hydralazine Therapy Attenuates Heart Failure With Preserved Ejection Fraction Severity in a "2-Hit" Murine Model. J Am Heart Assoc 2023; 12:e028480. [PMID: 36752224 PMCID: PMC10111505 DOI: 10.1161/jaha.122.028480] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 01/04/2023] [Indexed: 02/09/2023]
Abstract
Background Recent studies have suggested that cardiac nitrosative stress mediated by pathological overproduction of nitric oxide (NO) via inducible NO synthase (iNOS) contributes to the pathogenesis of heart failure with preserved ejection fraction (HFpEF). Other studies have suggested that endothelial NO synthase (eNOS) dysfunction and attenuated NO bioavailability contribute to HFpEF morbidity and mortality. We sought to further investigate dysregulated NO signaling and to examine the effects of a NO-based dual therapy (sodium nitrite+hydralazine) following the onset of HFpEF using a "2-hit" murine model. Methods and Results Nine-week-old male C57BL/6 N mice (n=15 per group) were treated concurrently with high-fat diet and N(ω)-nitro-L-arginine methyl ester (L-NAME) (0.5 g/L per day) via drinking water for 10 weeks. At week 5, mice were randomized into either vehicle (normal saline) or combination treatment with sodium nitrite (75 mg/L in the drinking water) and hydralazine (2.0 mg/kg IP, BID). Cardiac structure and function were monitored with echocardiography and invasive hemodynamic measurements. Cardiac mitochondrial respiration, aortic vascular function, and exercise performance were also evaluated. Circulating and myocardial nitrite were measured to determine the bioavailability of NO. Circulating markers of oxidative or nitrosative stress as well as systemic inflammation were also determined. Severe HFpEF was evident by significantly elevated E/E', LVEDP, and Tau in mice treated with L-NAME and HFD, which was associated with impaired NO bioavailability, mitochondrial respiration, aortic vascular function, and exercise capacity. Treatment with sodium nitrite and hydralazine restored NO bioavailability, reduced oxidative and nitrosative stress, preserved endothelial function and mitochondrial respiration, limited the fibrotic response, and improved exercise capacity, ultimately attenuating the severity of "two-hit" HFpEF. Conclusions Our data demonstrate that nitrite, a well-established biomarker of NO bioavailability and a physiological source of NO, is significantly reduced in the heart and circulation in the "2-hit" mouse HFpEF model. Furthermore, sodium nitrite+hydralazine combined therapy significantly attenuated the severity of HFpEF in the "2-hit" cardiometabolic HFpEF. These data suggest that supplementing NO-based therapeutics with a potent antioxidant and vasodilator agent may result in synergistic benefits for the treatment of HFpEF.
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Affiliation(s)
- Kyle B. LaPenna
- Cardiovascular Center of ExcellenceLouisiana State University Health Sciences CenterNew OrleansLA
- Department of Pharmacology and Experimental TherapeuticsLouisiana State University Health Sciences CenterNew OrleansLA
| | - Zhen Li
- Department of Cardiac SurgerySmidt Heart Institute, Cedars‐Sinai Medical CenterLos AngelesCA
| | - Jake E. Doiron
- Cardiovascular Center of ExcellenceLouisiana State University Health Sciences CenterNew OrleansLA
- Department of Pharmacology and Experimental TherapeuticsLouisiana State University Health Sciences CenterNew OrleansLA
| | - Thomas E. Sharp
- Cardiovascular Center of ExcellenceLouisiana State University Health Sciences CenterNew OrleansLA
- Department of Medicine, Section of CardiologyLouisiana State University Health Sciences CenterNew OrleansLA
| | - Huijing Xia
- Cardiovascular Center of ExcellenceLouisiana State University Health Sciences CenterNew OrleansLA
| | - Karl Moles
- Cardiovascular Center of ExcellenceLouisiana State University Health Sciences CenterNew OrleansLA
| | - Kashyap Koul
- Cardiovascular Center of ExcellenceLouisiana State University Health Sciences CenterNew OrleansLA
| | - John S. Wang
- Cardiovascular Center of ExcellenceLouisiana State University Health Sciences CenterNew OrleansLA
| | | | - Traci T. Goodchild
- Department of Cardiac SurgerySmidt Heart Institute, Cedars‐Sinai Medical CenterLos AngelesCA
| | - Ravi B. Patel
- Division of Cardiology, Department of Medicine and Bluhm Cardiovascular InstituteNorthwestern University Feinberg School of MedicineChicagoIL
| | - Sanjiv J. Shah
- Division of Cardiology, Department of Medicine and Bluhm Cardiovascular InstituteNorthwestern University Feinberg School of MedicineChicagoIL
| | - David J. Lefer
- Department of Cardiac SurgerySmidt Heart Institute, Cedars‐Sinai Medical CenterLos AngelesCA
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Kim HJ, Jo SH, Lee MH, Seo WW, Kim HL, Lee KY, Yang TH, Her SH, Lee BK, Park KH, Ahn Y, Rha SW, Gwon HC, Choi DJ, Baek SH. Nitrates vs. Other Types of Vasodilators and Clinical Outcomes in Patients with Vasospastic Angina: A Propensity Score-Matched Analysis. J Clin Med 2022; 11:jcm11123250. [PMID: 35743321 PMCID: PMC9225129 DOI: 10.3390/jcm11123250] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 06/02/2022] [Accepted: 06/05/2022] [Indexed: 12/04/2022] Open
Abstract
Although vasodilators are widely used in patients with vasospastic angina (VA), few studies have compared the long-term prognostic effects of different types of vasodilators. We investigated the long-term effects of vasodilators on clinical outcomes in VA patients according to the type of vasodilator used. Study data were obtained from a prospective multicenter registry that included patients who had symptoms suggestive of VA. Patients were classified into two groups according to use of nitrates (n = 239) or other vasodilators (n = 809) at discharge. The composite clinical events rate, including acute coronary syndrome (ACS), cardiac death, new-onset arrhythmia (including ventricular tachycardia and ventricular fibrillation), and atrioventricular block, was significantly higher in the nitrates group (5.3% vs. 2.2%, p = 0.026) during one year of follow-up. Specifically, the prevalence of ACS was significantly more frequent in the nitrates group (4.3% vs. 1.5%, p = 0.024). After propensity score matching, the adverse effects of nitrates remained. In addition, the use of nitrates at discharge was independently associated with a 2.69-fold increased risk of ACS in VA patients. In conclusion, using nitrates as a vasodilator at discharge can increase the adverse clinical outcomes in VA patients at one year of follow-up. Clinicians need to be aware of the prognostic value and consider prescribing other vasodilators.
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Affiliation(s)
- Hyun-Jin Kim
- Division of Cardiology, Department of Internal Medicine, Hanyang University College of Medicine, Seoul 04763, Korea;
| | - Sang-Ho Jo
- Division of Cardiology, Department of Internal Medicine, Hallym University Sacred Heart Hospital, Anyang-si 14068, Korea
- Correspondence: ; Tel.: +82-031-380-3722
| | - Min-Ho Lee
- Division of Cardiology, Department of Internal Medicine, Soonchunhyang University Seoul Hospital, Seoul 04401, Korea;
| | - Won-Woo Seo
- Division of Cardiology, Department of Internal Medicine, Kangdong Sacred Heart Hospital, Hallym University College of Medicine, Seoul 05355, Korea;
| | - Hack-Lyoung Kim
- Cardiovascular Center, Seoul National University Boramae Medical Center, Seoul 07061, Korea;
| | - Kwan Yong Lee
- Division of Cardiology, Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul 06591, Korea; (K.Y.L.); (S.H.B.)
| | - Tae-Hyun Yang
- Department of Cardiovascular Medicine, Busan Paik Hospital, Inje University, Busan 04551, Korea;
| | - Sung-Ho Her
- Department of Cardiovascular Medicine, St. Vincent’s Hospital, The Catholic University of Korea, Suwon 16249, Korea;
| | - Byoung-Kwon Lee
- Department of Cardiovascular Medicine, Gangnam Severance Hospital, Yonsei University, Seoul 06273, Korea;
| | - Keun-Ho Park
- Division of Cardiology, Department of Internal Medicine, Chosun Medical Center, Gwangju 61453, Korea;
| | - Youngkeun Ahn
- Department of Cardiology, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju 61469, Korea;
| | - Seung-Woon Rha
- Department of Cardiovascular Medicine, Guro Hospital, Korea University, Seoul 08308, Korea;
| | - Hyeon-Cheol Gwon
- Department of Cardiovascular Medicine, Samsung Medical Center, Sungkyunkwan University, Seoul 06351, Korea;
| | - Dong-Ju Choi
- Division of Cardiology, Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam 13620, Korea;
| | - Sang Hong Baek
- Division of Cardiology, Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul 06591, Korea; (K.Y.L.); (S.H.B.)
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Kim CH, Park TK, Cho SW, Oh MS, Lee DH, Seong CS, Gwag HB, Lim AY, Yang JH, Song YB, Hahn JY, Choi JH, Lee SH, Gwon HC, Ahn J, Carriere KC, Choi SH. Impact of different nitrate therapies on long-term clinical outcomes of patients with vasospastic angina: A propensity score-matched analysis. Int J Cardiol 2018; 252:1-5. [PMID: 29249418 DOI: 10.1016/j.ijcard.2017.07.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 06/16/2017] [Accepted: 07/11/2017] [Indexed: 01/12/2023]
Abstract
BACKGROUND Despite the short-term vasodilatory effects of nitrates, the prognostic effects of long-term nitrate therapy in patients with vasospastic angina (VSA) remains unclear. We investigated the prognostic impact of chronic nitrate therapy in VSA patients. METHODS Between January 2003 and December 2014, a total of 1154 VSA patients proven by ergonovine provocation tests were classified into nitrate (n=676) and non-nitrate (n=478) groups according to prescriptions for oral nitrates, including isosorbide mononitrate (ISMN) and nicorandil. The primary outcome was major adverse cardiovascular events (MACE), defined as a composite of cardiac death, myocardial infarction, any revascularization, or rehospitalization due to recurrent angina. RESULTS The nitrate group was found to have a higher risk of MACE (22.9% vs. 17.6%, hazard ratio [HR] 1.32, 95% confidence interval [CI] 1.01-1.73, p=0.043) than the non-nitrate group. After propensity score matching, the nitrate group had greater risks of MACE (HR 1.32, 95%CI 1.01-1.73, p=0.049). Patients who received the immediate-release formula of ISMN (HR 1.80, 95%CI 1.35-2.39, p<0.001) or were administered any forms of ISMN other than at bedtime (HR 1.90, 95%CI 1.41-2.57, p<0.001) had a significantly higher risk of MACE compared with the non-nitrate group. Nicorandil was shown to have a neutral effect on VSA patients (HR 1.11, 95%CI 0.73-1.69, p=0.62). CONCLUSIONS The long-term use of nitrate therapy was associated with increased risk of adverse cardiac events in VSA patients. The use of immediate-release ISMN or the administration of ISMN other than at bedtime was related with poor outcomes of VSA patients.
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Affiliation(s)
- Chung Hun Kim
- Division of Cardiology, Department of Internal Medicine, Hyemin General Hospital, Seoul, Republic of Korea
| | - Taek Kyu Park
- Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Republic of Korea
| | - Sung Woo Cho
- Division of Cardiology, Department of Internal Medicine, Inje University, College of Medicine, Seoul Paik Hospital, Seoul, Republic of Korea
| | - Min Seok Oh
- Cardiovascular Center, Department of Internal Medicine, Bundang Jesaeng Hospital, Daejin Medical Center, Gyeonggi-do, Republic of Korea
| | - Da Hyon Lee
- Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Republic of Korea
| | - Choong Sil Seong
- Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Republic of Korea
| | - Hye Bin Gwag
- Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Republic of Korea
| | - A Young Lim
- Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Republic of Korea
| | - Jeong Hoon Yang
- Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Republic of Korea
| | - Young Bin Song
- Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Republic of Korea
| | - Joo-Yong Hahn
- Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Republic of Korea
| | - Jin-Ho Choi
- Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Republic of Korea
| | - Sang Hoon Lee
- Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Republic of Korea
| | - Hyeon-Cheol Gwon
- Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Republic of Korea
| | - Joonghyun Ahn
- Department of Biostatistics and Clinical Epidemiology, Samsung Medical Center, Seoul, Republic of Korea
| | - K C Carriere
- Department of Biostatistics and Clinical Epidemiology, Samsung Medical Center, Seoul, Republic of Korea; Department of Mathematical and Statistical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Seung-Hyuk Choi
- Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Republic of Korea.
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Münzel T, Daiber A. Inorganic nitrite and nitrate in cardiovascular therapy: A better alternative to organic nitrates as nitric oxide donors? Vascul Pharmacol 2018; 102:1-10. [DOI: 10.1016/j.vph.2017.11.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 11/11/2017] [Accepted: 11/12/2017] [Indexed: 01/08/2023]
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Mao M, Varadarajan S, Fukai T, Bakhshi FR, Chernaya O, Dudley SC, Minshall RD, Bonini MG. Nitroglycerin tolerance in caveolin-1 deficient mice. PLoS One 2014; 9:e104101. [PMID: 25158065 PMCID: PMC4144835 DOI: 10.1371/journal.pone.0104101] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 07/06/2014] [Indexed: 11/18/2022] Open
Abstract
Nitrate tolerance developed after persistent nitroglycerin (GTN) exposure limits its clinical utility. Previously, we have shown that the vasodilatory action of GTN is dependent on endothelial nitric oxide synthase (eNOS/NOS3) activity. Caveolin-1 (Cav-1) is known to interact with NOS3 on the cytoplasmic side of cholesterol-enriched plasma membrane microdomains (caveolae) and to inhibit NOS3 activity. Loss of Cav-1 expression results in NOS3 hyperactivation and uncoupling, converting NOS3 into a source of superoxide radicals, peroxynitrite, and oxidative stress. Therefore, we hypothesized that nitrate tolerance induced by persistent GTN treatment results from NOS3 dysfunction and vascular toxicity. Exposure to GTN for 48-72 h resulted in nitrosation and depletion (>50%) of Cav-1, NOS3 uncoupling as measured by an increase in peroxynitrite production (>100%), and endothelial toxicity in cultured cells. In the Cav-1 deficient mice, NOS3 dysfunction was accompanied by GTN tolerance (>50% dilation inhibition at low GTN concentrations). In conclusion, GTN tolerance results from Cav-1 modification and depletion by GTN that causes persistent NOS3 activation and uncoupling, preventing it from participating in GTN-medicated vasodilation.
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Affiliation(s)
- Mao Mao
- Department of Medicine-Section of Cardiology, University of Illinois at Chicago, Chicago, Illinois, United States of America
- Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois, United States of America
- Department of Pathology, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Sudhahar Varadarajan
- Department of Medicine-Section of Cardiology, University of Illinois at Chicago, Chicago, Illinois, United States of America
- Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Tohru Fukai
- Department of Medicine-Section of Cardiology, University of Illinois at Chicago, Chicago, Illinois, United States of America
- Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Farnaz R. Bakhshi
- Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Olga Chernaya
- Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Samuel C. Dudley
- Department of Medicine-Section of Cardiology, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Richard D. Minshall
- Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois, United States of America
- Department of Anesthesiology, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Marcelo G. Bonini
- Department of Medicine-Section of Cardiology, University of Illinois at Chicago, Chicago, Illinois, United States of America
- Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois, United States of America
- * E-mail:
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Cecelja M, Jiang B, McNeill K, Kato B, Ritter J, Spector T, Chowienczyk P. Increased wave reflection rather than central arterial stiffness is the main determinant of raised pulse pressure in women and relates to mismatch in arterial dimensions: a twin study. J Am Coll Cardiol 2009; 54:695-703. [PMID: 19679247 DOI: 10.1016/j.jacc.2009.04.068] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2008] [Revised: 04/06/2009] [Accepted: 04/14/2009] [Indexed: 10/20/2022]
Abstract
OBJECTIVES Our aim was to examine the relative contributions of the first systolic shoulder (P1) and augmentation pressure (DeltaP(aug)) to central pulse pressure (cPP), their relation to central arterial stiffness (pulse wave velocity [PWV]) and arterial diameters, and their respective heritability estimates. BACKGROUND cPP is augmented above P1 by DeltaP(aug) due to pressure waves reflected from the periphery of the circulation. METHODS Women (n = 496) from the Twins UK adult twin registry (112 monozygotic, 135 dizygotic pairs) age 21 to 81 years were studied. cPP, P1, and DeltaP(aug) were estimated using the SphygmoCor system (Atcor, West Ryde, Australia) from transformed radial waveforms. Carotid-femoral PWV was measured using the same system. Aortic and femoral artery diameters were measured by ultrasonography. Heritability was estimated using structural equation modeling. RESULTS P1 and DeltaP(aug) accounted for 22% and 76%, respectively, of the variance in cPP. After adjustment for mean arterial pressure and heart rate, P1 strongly independently positively correlated with PWV (standardized regression coefficient, beta = 0.4, p < 0.0001), whereas DeltaP(aug) did not independently correlate with PWV but independently negatively correlated with the ratio of the diameter of the femoral to that of the abdominal aorta (beta = -0.12, p < 0.001). Estimates of heritability (h(2)) of cPP, PWV, P1, and DeltaP(aug) were 0.43, 0.34, 0.31, and 0.62, respectively, after adjustment for mean arterial pressure and heart rate. CONCLUSIONS These results suggest that, in women, DeltaP(aug) is highly heritable, is associated with the ratio of distal to proximal arterial diameters, and, independent of PWV, is a major determinant of cPP.
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Affiliation(s)
- Marina Cecelja
- King's College London, Cardiovascular Division, London, UK
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Störk T, Eichstädt H, Möckel M, Gareis R, Bodemann T, Müller R. Hemodynamic action of captopril in coronary patients with heart failure tolerant to nitroglycerin. Clin Cardiol 2009; 20:999-1004. [PMID: 9422837 PMCID: PMC6655751 DOI: 10.1002/clc.4960201205] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND At present there is little dispute that clinical tolerance of organic nitrates occurs during long-term treatment of patients with stable angina pectoris and congestive heart failure. HYPOTHESIS Captopril exerts a favorable hemodynamic effect in coronary patients with heart failure who are clinically tolerant to nitroglycerin. METHODS Development of nitrate tolerance was observed during intravenous nitroglycerin treatment (10 mg/h) in 16 of 19 patients (7 women, 12 men; mean age 56 +/- 8 years) with coronary heart disease [stenosis > or = 75%, New York Heart Association (NYHA) classes II-III). The criterion applied was a loss of efficacy of at least 50% with regard to mean pulmonary capillary wedge pressure compared with the maximum effect of nitrate. The effect of captopril (50 mg p.o.) was determined in a blank test. Captopril (50 mg p.o.) was administered again at the stage of clinically manifest nitrate tolerance. RESULTS Compared with the effect of captopril alone, significantly more pronounced reductions in mean pulmonary capillary wedge pressure (33% compared with 27%) and in mean pulmonary arterial pressure (36% compared with 17%) and significantly greater increases in cardiac index (14% compared with 7%) and stroke work index (34% compared with 18%) (p < 0.05 in each case; Wilcoxon test for linked random samples) were measured. Maintaining nitroglycerin infusion, the effect of captopril (at least 90% of the maximum effect) lasted for 123 +/- 24 min. The baseline values (at least 75% decline in the effect of captopril) were only reached after 369 +/- 34 min. CONCLUSION The results document a favorable hemodynamic effect of captopril in nitrate tolerance which is significantly better than that of captopril alone.
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Affiliation(s)
- T Störk
- Karl Olga Krankenhaus, Department of Cardiology and Intensive Care, Stuttgart, Germany
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Kanamasa K, Hayashi T, Takenaka T, Kimura A, Ikeda A, Ishikawa K. Continuous long-term dosing with oral slow-release isosorbide dinitrate does not reduce incidence of cardiac events in patients with healed myocardial infarction. Clin Cardiol 2009; 24:608-14. [PMID: 11558843 PMCID: PMC6655057 DOI: 10.1002/clc.4960240908] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND In the short term, isosorbide dinitrate (ISDN) is considered to be therapeutically effective. The long-term effects of treatment with slow-release ISDN are less clear. HYPOTHESIS The study was undertaken to investigate the effects of continuous, long-term dosing with oral slow-release ISDN on the incidence of cardiac events in patients with healed myocardial infarction (MI). The study was carried out in accordance with the intention-to-treat principle. METHODS In all, 1.102 in- and outpatients, of either gender, with healed MI were randomly divided into groups treated with ISDN (n = 470) and not treated with ISDN (n = 632). Patients in the ISDN group received a continuous regimen of 20 mg of oral, long-acting ISDN three times a day, after meals. The mean observation period was 15.0 +/- 18.5 months. The primary endpoints were nonfatal and fatal recurrent MI, death from congestive heart failure, and sudden death. RESULTS There were no significant differences in the baseline characteristics of the patients in the ISDN and no-treatment groups; nevertheless, significantly more patients in the ISDN group experienced cardiac events. In the ISDN group, 35 patients (7.4%) experienced cardiac events during the observation period, versus only 28 patients (4.4%) in the no-treatment group (p < 0.05; odds ratio 1.74; 95% confidence interval 1.04-2.90). CONCLUSION Continuous long-term dosing with oral, slow-release ISDN does not reduce and probably increases the incidence of cardiac events among patients with healed MI.
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Affiliation(s)
- K Kanamasa
- The First Department of Internal Medicine, Kinki University School of Medicine, Osaka, Japan.
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Koyuncu A, Bagcivan I, Sarac B, Aydin C, Yildirim S, Sarioglu Y. Lack of nitrate tolerance in isosorbide dinitrate- and sodium nitroprusside-induced relaxation of rabbit internal anal sphincter. World J Gastroenterol 2008; 14:4667-71. [PMID: 18698681 PMCID: PMC2738791 DOI: 10.3748/wjg.14.4667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the tolerance development against the relaxant effect of nitric oxide donating drug isosorbide dinitrate (ISDN) and sodium nitroprusside (SNP) in internal anal sphincter (IAS) smooth muscle.
METHODS: Relaxation responses of ISDN, and electrical field stimulation (EFS) were obtained before and after tolerance induction by ISDN incubation.
RESULTS: ISDN (10-7-10-4 mol/L) and SNP (10-8-10-4 mol/L) caused a concentration-dependent relaxation on the basal tonus of the isolated rabbit IAS strips. After a period of 2 h incubation of the 6 x 10-4 mol/L ISDN the relaxation effects of ISDN and SNP did not change compared to control strips. EFS evoked frequency-dependent relaxation in internal anal sphincter smooth muscle and Emax obtained from control strips were not changed in ISDN tolerance-inducing condition. In this study nitrate tolerance was not observed in rabbit IAS smooth muscle.
CONCLUSION: This result shows that nitric oxide donating drugs relaxes the internal anal sphincter of the rabbits without the development of tolerance.
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Tsou PS, Addanki V, Fung HL. Dissociation between superoxide accumulation and nitroglycerin-induced tolerance. J Pharmacol Exp Ther 2008; 327:97-104. [PMID: 18653825 DOI: 10.1124/jpet.108.138784] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
We hypothesize that superoxide (O(2)(*-)) accumulation is not a crucial causative factor in inducing nitroglycerin (NTG) tolerance. In LLC-PK1 cells, pre-exposure to NTG resulted in increased O(2)(*-) accumulation and reduced cGMP response to NTG versus vehicle control. O(2)(*-) stimulated by NTG was reduced by oxypurinol (100 microM), a xanthine oxidase inhibitor. Exposure to angiotensin II (Ang II) increased O(2)(*-) but did not reduce cGMP response. The O(2)(*-) scavenger tiron reduced Ang II-induced O(2)(*-) production but did not increase NTG-stimulated cGMP production. Using p47(phox-/-) and gp91(phox-/-) mice versus their respective wild-type controls (WT), we showed that aorta from mice null of these critical NADPH oxidase subunits exhibited similar vascular tolerance after NTG dosing (20 mg/kg s.c., t.i.d. for 3 days), as indicated by their ex vivo pEC(50) and cGMP accumulation upon NTG challenge. In vitro aorta O(2)(*-) production was enhanced by NTG incubation in both p47(phox) null and WT mice. Pre-exposure of isolated mice aorta to 100 microM NTG for 1 h resulted in vascular tolerance toward NTG and increased O(2)(*-) accumulation. Oxypurinol (1 mM) reduced O(2)(*-) but did not attenuate vascular tolerance. These results suggest that O(2)(*-) does not initiate either in vitro and in vivo NTG tolerance, and that the p47(phox) and gp91(phox) subunits of NADPH oxidase are not critically required. Increased O(2)(*-) accumulation may be an effect, rather than an initiating cause, of NTG tolerance.
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Affiliation(s)
- Pei-Suen Tsou
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY 14260-1200, USA
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Peng J, Li YJ. New insights into nitroglycerin effects and tolerance: role of calcitonin gene-related peptide. Eur J Pharmacol 2008; 586:9-13. [PMID: 18367169 DOI: 10.1016/j.ejphar.2008.02.039] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2007] [Revised: 01/31/2008] [Accepted: 02/13/2008] [Indexed: 11/17/2022]
Abstract
It has been shown that calcitonin gene-relate peptide plays an extensive role in cardiovascular system. CGRP is a potent vasodilator and plays an important role in mediation of nitroglycerin-induced vascular relaxation. Recently, calcitonin gene-relate peptide is emerging as a potential player in nitroglycerin tolerance. There is increasing evidence that the decreased depressor effect of nitroglycerin in tolerant states is closely related to a decrease in calcitonin gene-relate peptide release. The reduced release of calcitonin gene-relate peptide in nitroglycerin tolerance is associated with the decreased nitroglycerin biotransformation due to the mitochondrial dysfunction. Recent work has been shown that the inhibited activity of mitochondrial isoform of aldehyde dehydrogenase and the upregulation of phosphodiesterase 1A1 are the key factors that lead to the decreased nitroglycerin biotransformation in nitroglycerin tolerance, with a subsequently reduced release of calcitonin gene-relate peptide.
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Affiliation(s)
- Jun Peng
- Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China
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12
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Long-Term Nitrate Use in Acute Myocardial Infarction (The Heart Institute of Japan, Department of Cardiology Nitrate Evaluation Program). Cardiovasc Drugs Ther 2008; 22:177-84. [DOI: 10.1007/s10557-008-6089-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2007] [Accepted: 01/24/2008] [Indexed: 10/22/2022]
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13
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Madhani M, Patra AK, Miller TW, Eroy-Reveles AA, Hobbs AJ, Fukuto JM, Mascharak PK. Biological activity of designed photolabile metal nitrosyls: light-dependent activation of soluble guanylate cyclase and vasorelaxant properties in rat aorta. J Med Chem 2007; 49:7325-30. [PMID: 17149862 DOI: 10.1021/jm0604629] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The biological and pharmacological utility of nitric oxide (NO) has led to the development of many classes of NO-donor compounds as both research tools and therapeutic agents. Many donors currently in use rely on thermal decomposition or bioactivation for the release of NO. We have developed several photolabile metal-nitrosyl donors that release NO when exposed to either visible or UV light. Herein, we show that these donors are capable of activating the primary "NO receptor", soluble guanylate cyclase (sGC), in a light-dependent fashion leading to increases in cGMP. Moreover, we demonstrate that these donors are capable of eliciting light-dependent increases of cGMP in smooth muscle cells and vasorelaxation of rat aortic smooth muscle tissue, all effects that are attributed to activation of sGC. The potential utility of these compounds as drugs and/or research tools is discussed.
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MESH Headings
- Animals
- Aorta/drug effects
- Aorta/physiology
- Cells, Cultured
- Cyclic GMP/biosynthesis
- Enzyme Activation
- Guanylate Cyclase/chemistry
- Guanylate Cyclase/isolation & purification
- In Vitro Techniques
- Iron
- Light
- Manganese
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Nitric Oxide Donors/chemical synthesis
- Nitric Oxide Donors/pharmacology
- Nitric Oxide Donors/radiation effects
- Organometallic Compounds/chemical synthesis
- Organometallic Compounds/pharmacology
- Organometallic Compounds/radiation effects
- Rats
- Receptors, Cytoplasmic and Nuclear/chemistry
- Receptors, Cytoplasmic and Nuclear/isolation & purification
- Ruthenium
- Soluble Guanylyl Cyclase
- Structure-Activity Relationship
- Vasodilation/drug effects
- Vasodilator Agents/chemical synthesis
- Vasodilator Agents/pharmacology
- Vasodilator Agents/radiation effects
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Affiliation(s)
- Melanie Madhani
- Wolfson Institute for Biomedical Research, University College London, Cruciform Building, Gower Street, London WC1E 6AE, United Kingdom
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14
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Morii H, Naito N, Nakano K, Kanamasa K. Inhibition of nitrate tolerance without reducing vascular response during eccentric dosing of nitrates. Hypertens Res 2007; 29:797-804. [PMID: 17283867 DOI: 10.1291/hypres.29.797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
It has been reported that the nitrate tolerance related to continuous dosing of nitrates reduces drug efficacy, and therefore eccentric dosing of nitrates is recommended. In this study, we investigated the appearance of nitrate tolerance related to continuous dosing of nitrates and prevention of nitrate tolerance during eccentric dosing by comparing the grade of coronary dilatation after sublingual nitroglycerin. Of 26 patients with ischemic heart disease who underwent elective cardiac catheterization, 8 patients were continuously administered nitrates, 8 patients were eccentrically administered nitrates, and 10 patients were not treated. We compared the coronary response to sublingual nitroglycerin among the 3 groups. In a coronary vessel without significant stenosis, the coronary vessel area, coronary lumen area, and mean coronary blood flow velocity after sublingual nitroglycerin were measured using intravascular ultrasound (IVUS). In the continuous dosing group, the maximal rate of change in the vessel area after sublingual nitroglycerin was 105 +/- 1 (mean +/- SEM) %, significantly lower than those in the untreated group and the eccentric dosing group (114 +/- 2%, 114 +/- 2%) (p < 0.01, respectively). In conclusion, eccentric dosing of nitrates inhibited the appearance of nitrate tolerance without reducing vascular response.
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Affiliation(s)
- Hideki Morii
- Department of Vascular and Geriatric Medicine, Kinki University School of Medicine, Osaka-Sayama, Japan
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15
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Minamiyama Y, Takemura S, Hai S, Suehiro S, Okada S, Funae Y. Nicorandil elevates tissue cGMP levels in a nitric-oxide-independent manner. J Pharmacol Sci 2007; 103:33-9. [PMID: 17202748 DOI: 10.1254/jphs.fp0061003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
The K(+) channel opener nicorandil is a hybrid compound that contains nitrate in its structure. It has been reported that nicorandil can relax vascular tissue in vitro via a mechanism that involves activation of K(ATP) channels and stimulation of soluble guanylyl cyclase. However, it is not known whether the increase of cGMP levels occurs through an elevation of nitric oxide (NO). The aim of the present study was to determine whether NO release was a direct effect of nicorandil. We reported here that nicorandil did not generate NO using ozone chemiluminescence detection methods in human or rat liver microsomes (P450-rich fractions) with addition of NADPH. However, nicorandil elevated cGMP levels in rat liver, aorta, and human coronary smooth muscle cells in vitro. The elevation was not inhibited by the NO trapping agent carboxy-2-phenyl-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide (carboxy-PTIO). These results suggest that nicorandil elevates cGMP without NO generation.
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Affiliation(s)
- Yukiko Minamiyama
- Department of Anti-Aging Food Sciences, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Shikata-cho, Yokohama 700-8558, Japan. ,jp
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16
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Abrams J, Schroeder J, Frishman WH, Freedman J. Pharmacologic Options for Treatment of Ischemic Disease. Cardiovasc Ther 2007. [DOI: 10.1016/b978-1-4160-3358-5.50011-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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17
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Madhani M, Okorie M, Hobbs AJ, MacAllister RJ. Reciprocal regulation of human soluble and particulate guanylate cyclases in vivo. Br J Pharmacol 2006; 149:797-801. [PMID: 17016498 PMCID: PMC2014653 DOI: 10.1038/sj.bjp.0706920] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND & PURPOSE We demonstrated previously that reciprocal regulation of soluble (sGC) and particulate (pGC) guanylate cyclases by NO and natriuretic peptides coordinates cyclic cGMP-mediated vasodilatation in vitro. Herein, we investigated whether such an interaction contributes to vascular homeostasis in mice and humans in vivo. EXPERIMENTAL APPROACH Mean arterial blood pressure (MABP) changes in anaesthetized mice were monitored in response to i.v. administration of cGMP- and cAMP-dependent vasodilators in wild-type (WT), endothelial NO synthase (eNOS) and natriuretic peptide receptor (NPR)-A knockout mice. Forearm blood flow (FBF) in response to intra-brachial infusion of ANP (25, 50, 100, 200 pmol min(-1)) in the absence and presence of the NOS inhibitor NG-methyl-L-arginine (L-NMA; 4 micromol min(-1)) and the control constrictor noradrenaline (240 pmol min(-1)) was assessed in healthy volunteers. KEY RESULTS Sodium nitroprusside (SNP; NO-donor) and atrial natriuretic peptide (ANP) produced dose-dependent reductions in MABP in WT animals that were significantly enhanced in eNOS KO mice. In NPR-A K mice, SNP produced a dose-dependent reduction in MABP that was significantly greater than that in WT mice. Responsiveness to the cAMP-dependent vasodilator epoprostenol was similar in WT, eNOS KO and NPR-A KO animals. ANP caused vasodilatation of the forearm resistance vasculature that was significantly greater in individuals lacking endothelium-derived NO (i.e. L-NMA treated). CONCLUSIONS & IMPLICATIONS These data demonstrate that crosstalk occurs between the NO-sGC and ANP-pGC pathways to regulate cGMP-dependent vasodilatation in vivo in both mice and humans. These findings have implications for understanding the link between natriuretic peptide activity and cardiovascular risk.
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Affiliation(s)
- M Madhani
- Wolfson Institute for Biomedical Research, University College London London, UK
| | - M Okorie
- Centre for Clinical Pharmacology, University College London London, UK
| | - A J Hobbs
- Wolfson Institute for Biomedical Research, University College London London, UK
- Author for correspondence:
| | - R J MacAllister
- Centre for Clinical Pharmacology, University College London London, UK
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18
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Breschi MC, Calderone V, Digiacomo M, Macchia M, Martelli A, Martinotti E, Minutolo F, Rapposelli S, Rossello A, Testai L, Balsamo A. New NO-Releasing Pharmacodynamic Hybrids of Losartan and Its Active Metabolite: Design, Synthesis, and Biopharmacological Properties. J Med Chem 2006; 49:2628-39. [PMID: 16610806 DOI: 10.1021/jm0600186] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In a preliminary work, we reported two NO-sartans, possessing the characteristics of an AT(1) antagonist and a "slow NO donor", obtained by adding NO-donor side chains to losartan 1. The NO release from an NO-sartan should be modulated in order to strengthen the antihypertensive activity of the native drug and to ensure additional effects, such as the antiplatelet and anti-ischemic ones. To obtain a collection of prototypical NO-sartans, showing different rates of NO release, new NO-donor moieties have been linked to 1 or its active metabolite 2 (EXP 3174). Almost all the synthesized compounds exhibited both AT(1)-antagonist and NO-mediated vasorelaxing properties, with a wide range of NO-releasing rates. Further pharmacological investigation on compound 4a showed that it possessed antihypertensive and cardiac antihypertrophic effects similar to those of the reference AT(1)-blocking or ACE-inhibiting drugs. Furthermore, the additional anti-ischemic cardio-protective properties and antiplatelet effects of 4a have been preliminarily investigated.
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Affiliation(s)
- Maria C Breschi
- Dipartimento di Psichiatria, Neurobiologia, Farmacologia e Biotecnologie, Università di Pisa, Via Bonanno 6, 56126 Pisa, Italy
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19
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Zoma WD, Baker RS, Mershon JL, Clark KE. Hemodynamic effects of acute and repeated exposure to raloxifene in ovariectomized sheep. Am J Physiol Heart Circ Physiol 2006; 291:H1216-25. [PMID: 16517945 DOI: 10.1152/ajpheart.00666.2005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We hypothesize that administration of acute and daily doses of raloxifene will have significant effects on ovine coronary and uterine hemodynamics and that these changes are estrogen receptor dependent. Eleven ovariectomized sheep were instrumented to measure mean arterial pressure, heart rate (HR), cardiac output (CO), and coronary (CBF) and uterine artery blood flows (UBF). A dose-response curve was generated for raloxifene (1, 3, and 10 microg/kg) and compared with a standard dose of estradiol-17beta (1 microg/kg) given intravenously. In a second group of animals, raloxifene (10 microg.kg-1.day-1) was administered intravenously for 14 consecutive days, and cardiovascular responses were compared with a group of animals administered estradiol-17beta (10 microg/kg) daily for the same period. To determine whether raloxifene-related vascular responses were estrogen receptor (ER) mediated, the animals were pretreated with estrogen antagonist ICI-182,780 given intravenously. Finally, RT-PCR was preformed to determine the presence of ERalpha and ERbeta mRNA in ovine coronary and uterine vessels. Raloxifene increased CBF and UBF dose dependently with a parallel decrease in the associated vascular resistances. Acute cardiovascular responses to daily doses of raloxifene and estradiol-17beta were sustainable. In contrast to estradiol-17beta, which significantly increases CO by increasing HR but not stroke volume, raloxifene significantly increased stroke volume without a significant parallel increase in HR. ICI-182,780 abolished raloxifene-induced hemodynamic responses, and ERalpha and ERbeta mRNA are present in both ovine coronary and uterine vessels. Hence, the hemodynamic effects of raloxifene are dose dependent, sustainable, and estrogen receptor mediated.
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Affiliation(s)
- Willie D Zoma
- Department of Obstetrics and Gynecology, P.O. Box 670526, University of Cincinnati College of Medicine, 231 Albert Sabin Way, Cincinnati, OH 45267-0526, USA
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20
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Abstract
The vascular endothelium synthesises the vasodilator and anti-aggregatory mediator nitric oxide (NO) from L-arginine. This action is catalysed by the action of NO synthases, of which two forms are present in the endothelium. Endothelial (e)NOS is highly regulated, constitutively active and generates NO in response to shear stress and other physiological stimuli. Inducible (i)NOS is expressed in response to immunological stimuli, is transcriptionally regulated and, once activated, generates large amounts of NO that contribute to pathological conditions. The physiological actions of NO include the regulation of vascular tone and blood pressure, prevention of platelet aggregation and inhibition of vascular smooth muscle proliferation. Many of these actions are a result of the activation by NO of the soluble guanylate cyclase and consequent generation of cyclic guanosine monophosphate (cGMP). An additional target of NO is the cytochrome c oxidase, the terminal enzyme in the electron transport chain, which is inhibited by NO in a manner that is reversible and competitive with oxygen. The consequent reduction of cytochrome c oxidase leads to the release of superoxide anion. This may be an NO-regulated cell signalling system which, under certain circumstances, may lead to the formation of the powerful oxidant species, peroxynitrite, that is associated with a variety of vascular diseases.
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Affiliation(s)
- S Moncada
- The Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK.
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21
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Braam B, de Roos R, Dijk A, Boer P, Post JA, Kemmeren PPCW, Holstege FCP, Bluysen HAR, Koomans HA. Nitric oxide donor induces temporal and dose-dependent reduction of gene expression in human endothelial cells. Am J Physiol Heart Circ Physiol 2004; 287:H1977-86. [PMID: 15242832 DOI: 10.1152/ajpheart.00323.2004] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The present study tested the hypothesis that acute increases in nitric oxide (NO) exert substantial influences on gene transcription in endothelial cells (ECs) via guanylyl cyclase (GC). Human umbilical veins ECs (HUVECs) were exposed to 0.1, 1, and 10 mM of sodium nitroprusside (SNP) for 4 h and to 1 mM SNP or 250 μM of ( Z)-1[ N-(2-aminoethyl)- N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate (DETA-NONOate) for 2, 4, 8, and 24 h. Also, cells were exposed to DETA-NONOate in the presence and absence of the GC inhibitor 1 H-[1,2,4]oxadiazolo-[4,3- a]quinoxalin-1-one (ODQ; 10 μM) for 4 h. RNA was isolated, reverse transcribed, Cy3 and Cy5 labeled, and analyzed using cDNA microarrays. Increasing doses of SNP predominantly depressed gene expression in HUVECs. Gene function was related to growth, adhesion, and cell structure. DETA-NONOate evoked a wave of expression changes (maximum at 4 h), with a remarkable downregulation of the transcription factors MSX1, RELB, and Egr-1. Both SNP- and DETA-NONOate-induced gene expression had faded after 24 h, despite continued elevation of cGMP in the medium. Coadministration of ODQ decreased many, but not all, of the transcriptional responses to DETA-NONOate. NO pronouncedly depressed EC gene expression, in particular of transcription factors. The observation that many, but not all, transcriptional changes induced by NO could be inhibited by inhibition of GC indicates the presence of GC-independent NO actions on gene expression. Thus EC gene expression responds to NO; however, the transcriptional response fades during prolonged exposure. This could allow the EC to respond to increased shear, without vigorous changes in gene expression.
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Affiliation(s)
- Branko Braam
- Dept. of Nephrology and Hypertension, F03.226, Univ. Medical Center Utrecht, 3508 GA Utrecht, The Netherlands.
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22
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Thatcher GRJ, Nicolescu AC, Bennett BM, Toader V. Nitrates and NO release: contemporary aspects in biological and medicinal chemistry. Free Radic Biol Med 2004; 37:1122-43. [PMID: 15451053 DOI: 10.1016/j.freeradbiomed.2004.06.013] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2004] [Accepted: 06/03/2004] [Indexed: 11/28/2022]
Abstract
Nitroglycerine has been used clinically in the treatment of angina for 130 years, yet important details on the mechanism of action, biotransformation, and the associated phenomenon of nitrate tolerance remain unanswered. The biological activity of organic nitrates can be said to be nitric oxide mimetic, leading to recent, exciting progress in realizing the therapeutic potential of nitrates. Unequivocally, nitroglycerine and most other organic nitrates, including NO-NSAIDs, do not behave as NO donors in the most fundamental action: in vitro activation of sGC to produce cGMP. The question as to whether the biological activity of nitrates results primarily or exclusively from NO donation will not be satisfactorily answered until the location, the apparatus, and the mechanism of reduction of nitrates to NO are defined. Similarly, the therapeutic potential of nitrates will not be unlocked until this knowledge is attained. Aspects of the therapeutic and biological activity of nitrates are reviewed in the context of the chemistry of nitrates and the elusive efficient 3e- reduction required to generate NO.
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Affiliation(s)
- Gregory R J Thatcher
- Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, 833 S. Wood Street, Chicago, IL 60612-7231, USA.
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23
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Fayers KE, Cummings MH, Shaw KM, Laight DW. Nitrate tolerance and the links with endothelial dysfunction and oxidative stress. Br J Clin Pharmacol 2004; 56:620-8. [PMID: 14616421 PMCID: PMC1884304 DOI: 10.1046/j.1365-2125.2003.01946.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Identification of nitric oxide as the molecule responsible for endothelial dependant vasodilatation has led to an explosion of interest in endothelial function. Oxidative stress has been identified as an important factor in the development of tolerance to organic nitrates. This review examines the evidence supporting this recently developed theory and how mechanisms of nitrate tolerance may link with the wider picture of primary nitric oxide resistance.
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Affiliation(s)
- Katherine E Fayers
- Academic Department of Diabetes and Endocrinology, Queen Alexandra Hospital, Southwick Road, Cosham, Portsmouth, Hants, PO6 3LY, UK.
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24
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Abstract
Organic nitrates such as nitroglycerin (NTG) have been used as potent vasodilators in medicine for more than a century, but their biochemical mechanisms of action, particularly in relation to tolerance development, are still incompletely defined. Numerous candidate enzymes for NTG metabolism, as well as a multiplicity of tolerance mechanisms, have been proposed in the literature, but a consolidating hypothesis that links these phenomena together has not appeared. Here, we outline a "thionitrate oxidation hypothesis," which attempts to link nitrate bioactivation and tolerance development in an overall mechanism. We also attempt to compare and contrast the proposed mechanism against existing theories of nitrate action and tolerance. Interactions between organic nitrates, which have been thought of as endothelium-independent agents, and the vascular endothelium and endothelial nitric oxide synthase (eNOS) are also discussed.
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Affiliation(s)
- Ho-Leung Fung
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York 14260-1200, USA.
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25
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Abstract
Rapid (premature) ejaculation (RE) is a very common sexual disorder. This condition may be primary or secondary to underlying disease. Control of RE has been primarily focused on behavioural therapy, topical anaesthetics, tricyclic antidepressants and selective serotonin reuptake inhibitors; however, an approved treatment does not exist. Recently, a number of clinical trials have studied the potential effectiveness of the phosphodiesterase (PDE)-5 inhibitor sildenafil in the treatment of RE. Results of most of these studies have been encouraging. Available data indicate that there is clinical, anatomical, physiological, pharmacological and genetic evidence to explain the efficacy of PDE5 inhibitors in RE. The rationale for the use of PDE5 inhibitors in the treatment of RE could be due to possible peripheral and central mechanisms. Possible peripheral ejaculation retarding capabilities may include modulation of the contractile response of the vas deferens (VD), seminal vesicles (SV), prostate and urethra, induction of a state of peripheral analgesia, and prolongation of the total duration of erection. Possible central mechanisms may involve lessening of the central sympathetic output. Furthermore, there is evidence from knockout mice to explain the efficacy of PDE5 inhibitors in RE. Mice lacking the gene for endothelial nitric oxide synthase develop a condition similar to RE. On the other hand, mice lacking the gene for heme oxygenase-2 develop a condition similar to delayed ejaculation. This review also discusses the findings against the use of these agents in RE. In conclusion, a review of the literature suggests the potential usefulness of PDE5 inhibitors as a promising line of therapy in RE but further studies are needed.
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26
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Abou-Mohamed G, Johnson JA, Jin L, El-Remessy AB, Do K, Kaesemeyer WH, Caldwell RB, Caldwell RW. Roles of superoxide, peroxynitrite, and protein kinase C in the development of tolerance to nitroglycerin. J Pharmacol Exp Ther 2003; 308:289-99. [PMID: 14563789 DOI: 10.1124/jpet.103.056119] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A current hypothesis states that tolerance to nitroglycerin (GTN) involves increased formation of superoxide (O2*-). Studies showing that inhibitors of protein kinase C (PKC) prevent tolerance to GTN suggest the involvement of PKC activation, which can also increase O2*-. We examined the roles of O2*-, peroxynitrite (ONOO-), and PKC activation in GTN tolerance. Pre-exposure of rat aortic rings to GTN (5 x 10(-4) M) for 2 h caused tolerance to the vasodilating effect of GTN, as evidenced by a substantial rightward shift of GTN concentration-relaxation curves. This shift was reduced by treatment of the rings with the antioxidants uric acid, vitamin C, or tempol or the PKC inhibitor chelerythrine. We also found that O2*- generation via xanthine/xanthine oxidase in the bath induced tolerance to GTN. However, responses to nitroprusside were not affected. In vivo tolerance produced in rats by 3-day i.v. infusion of GTN was also almost completely prevented by coinfusion of tempol. In bovine aortic endothelial cells (EC), addition of GTN produced a marked increase in tyrosine nitrosylation, indicating increased ONOO- formation. This action was blocked by prior treatment with uric acid, superoxide dismutase, NG-nitro-L-arginine methyl ester, or chelerythrine. We also demonstrated that GTN translocates the alpha- and epsilonPKC isoforms in EC. However, PKCzeta was not affected by GTN treatment. In conclusion, tolerance to GTN involves enhanced production of O2*- and ONOO- and activation of NO synthase. Furthermore, sustained activation of alpha- and epsilonPKC isozymes in EC by GTN may play a role in development of tolerance.
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Affiliation(s)
- G Abou-Mohamed
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta, Georgia 30912, USA
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27
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Nakae I, Matsumoto T, Omura T, Takashima H, Ohira N, Tarutani Y, Yasuda Y, Matsuo S, Koh T, Nakaura Y, Kinoshita M, Horie M. Endothelial modulation and tolerance development in the vasorelaxant responses to nitrate of rabbit aorta. Life Sci 2003; 73:3083-94. [PMID: 14550849 DOI: 10.1016/j.lfs.2003.04.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We investigated the endothelial modulations in nitrate tolerance in isolated rabbit aorta. Nitrate tolerance was induced by a 72-h treatment with transdermal nitroglycerin (NTG, 0.4 mg/h) in conscious rabbits, which was verified by a 20-fold increase in the EC50 values [NTG tolerance (6.1 +/- 0.8) x 10(-7) M vs control (3.0 +/- 0.6) x 10(-8) M]. The relaxations to NTG in tolerant and nontolerant aortic strips were enhanced when their endothelia were denuded [E(-)]. In the presence of endothelium [E(+)], NTG-tolerant vessels were not tolerant to acetylcholine (ACh), which can release endothelial nitric oxide (NO), exogenous NO or 8-bromo (Br)-cGMP. In NTG-tolerant and nontolerant vessels with endothelium, concentration-response curves for NO were the same as those in endothelium-absent tolerant vessels. In both NTG-tolerant and nontolerant vessels, treatment with superoxide dismutase (SOD, 20 units/ml), an O2-. scavenger, unaffected the responses to NTG reduced in the presence of endothelium, but treatment with NG-nitro-L-arginine methyl ester (L-NAME, 10(-4) M), an NO synthase (NOS) inhibitor, reversed these reductions. Thus, our data did not indicate that an increased endothelial superoxide O2-. production contributes to nitrate tolerance. Our study suggested that (i) an impaired biotransformation process from NTG to NO is responsible for the occurrence of nitrate tolerance and (ii) vascular response to NTG enhanced by endothelial removal is related to blocked endothelial NO release.
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Affiliation(s)
- Ichiro Nakae
- Department of Cardiovascular and Respiratory Medicine, Shiga University of Medical Science, Seta, Otsu 520-2192, Japan
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28
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Hirai N, Kawano H, Yasue H, Shimomura H, Miyamoto S, Soejima H, Kajiwara I, Sakamoto T, Yoshimura M, Nakamura H, Yodoi J, Ogawa H. Attenuation of nitrate tolerance and oxidative stress by an angiotensin II receptor blocker in patients with coronary spastic angina. Circulation 2003; 108:1446-50. [PMID: 12952843 DOI: 10.1161/01.cir.0000089092.61590.a8] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
BACKGROUND Nitrates are widely used to treat coronary artery disease, but their therapeutic value is compromised by the rapid development of tolerance. Recently, the renin-angiotensin system has been suggested to play an important role in the development of nitrate tolerance. METHODS AND RESULTS Sixty-four patients with coronary spastic angina were investigated to clarify the effect of angiotensin II type 1 receptor blocker (ARB) therapy on nitrate tolerance. Transdermal nitroglycerin (10 mg/d) and an ARB (candesartan, 8 mg/d) were administered to 21 patients (GTN+ARB group) for 3 days, whereas transdermal nitroglycerin and placebo were administered to 19 patients (GTN group). Another 18 patients were treated with placebo skin patches and placebo tablets for 3 days (control group). The brachial artery response to incremental doses of intravenous nitroglycerin (0.01, 0.1, and 1.0 micro;g/kg) was measured by ultrasound before and after transdermal nitroglycerin therapy. Before treatment, the arterial diameter was increased by nitroglycerin injection in each group. After treatment, the increase of arterial diameter was significantly suppressed in the GTN group but not in the control or GTN+ARB groups. The plasma level of thioredoxin (a marker of oxidative stress) was increased in the GTN group after treatment (P<0.01) but not in the control or GTN+ARB groups. CONCLUSIONS An ARB suppressed the development of nitrate tolerance during transdermal nitroglycerin therapy. These results suggest that increased oxidative stress induced by activation of angiotensin II may play an important role in the development of nitrate tolerance.
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Affiliation(s)
- Nobutaka Hirai
- Department of Cardiovascular Medicine, Kumamoto University School of Medicine, 1-1-1 Honjo, Kumamoto City 860-8556, Japan.
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Latini R, Staszewsky L, Maggioni AP, Marino P, Hernandez-Bernal F, Tognoni G, Labarta V, Gramenzi S, Bianchi F, Sarcina G, Cremonesi G, Nicolosi GL, Geraci E. Beneficial effects of angiotensin-converting enzyme inhibitor and nitrate association on left ventricular remodeling in patients with large acute myocardial infarction: the Delapril Remodeling after Acute Myocardial Infarction (DRAMI) trial. Am Heart J 2003; 146:133. [PMID: 12851621 DOI: 10.1016/s0002-8703(02)94777-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND In the large-scale trial, Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico-3 (GISSI-3), patients receiving the combination of lisinopril and glyceryl trinitrate benefited most from experimental therapy. Therefore, a multicenter, randomized, double-blind study, Delapril Remodeling After Acute Myocardial Infarction (DRAMI), was designed to assess (1) the possible additive beneficial effect on left ventricular remodeling of nitrates when combined with an angiotensin-converting enzyme inhibitor (ACEI), and (2) the tolerability of a new ACEI, delapril, in respect to lisinopril in patients with large myocardial infarction (MI). METHODS A total of 177 patients were randomized to receive delapril plus isosorbide-5-mononitrate (IS5MN) placebo, delapril plus IS5MN, lisinopril plus IS5MN placebo, or lisinopril plus IS5MN starting within the first 36 hours after the onset of symptoms and continuing for 3 months. RESULTS More than 80% of the patients showed extensive ST-segment changes and 36.7% had signs or symptoms of heart failure during the first 36 hours. Over 3 months, IS5MN reduced, by 76%, the increase in LVEDV (17.4 +/- 5.0 mL placebo vs 4.2 +/- 4.4 mL IS5MN, P =.0439), reversed the increase in LVESV (7.5 +/- 3.9 mL placebo vs -5.5 +/- 2.9 mL IS5MN, P =.0052), and increased the recovery of LVEF (1.9% +/- 1.3% placebo vs 6.7% +/- 1.2% IS5MN, P =.0119). Overall, 3-month mortality was 10.2%; the most frequent clinical events were new episodes of severe heart failure (18.1%), persistent hypotension (10.7%), and post-MI angina (18.1%), with no differences between treatment groups. CONCLUSIONS Administration for 3 months of IS5MN combined with an ACEI, both started within 36 hours from the onset of symptoms, was safe and effective in reducing LV dilation and dysfunction after MI. The 2 ACEIs, delapril and lisinopril, appeared to be equally well tolerated.
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Stanger O, Weger M. Interactions of Homocysteine, Nitric Oxide, Folate and Radicals in the Progressively Damaged Endothelium. Clin Chem Lab Med 2003; 41:1444-54. [PMID: 14656024 DOI: 10.1515/cclm.2003.222] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The endothelium exerts fundamental control over vascular tone, and injury to the endothelium followed by dysfunction is an early key event preceding manifestation of vessel pathology. Both elevated plasma homocysteine and low folate status have been identified as major and independent risk factors for atherosclerosis and have stirred an enormous and still increasing interest. The damaging effects of hyperhomocysteinemia on endothelial function are, at least in part, reversible through folate supplementation. Because of the inverse relationship between plasma folate and homocysteine levels, however, it is difficult to discriminate between their respective effects. Endothelial dysfunction refers mainly to reduced bioavailability of nitric oxide (NO), which is involved in homocysteinemediated vascular damage. Accumulating evidence further suggests that radical oxygen species are fundamentally involved in hyperhomocysteinemia. NO production is determined by cofactors such as tetrahydrobiopterin, which is oxidized and depleted in conditions of oxidant stress by peroxynitrite. Deficiency of tetrahydrofolate contributes to uncoupling, turning the NO synthase into a superoxide radical-producing enzyme. It appears that progression of vascular disease is likely to determine the multiple interactions between homocysteine, NO, oxygen radicals and folate. Folate has only recently been found to exert direct anti-oxidative effects and contribute to restoration of impaired NO metabolism. Understanding of the complex interactions between homocysteine, radicals, NO and folate offers promising perspectives in the individual treatment of vascular disease. Thus, preventive and therapeutic strategies may require a more distinct approach and better discrimination of target groups for greatest possible efficacy.
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Affiliation(s)
- Olaf Stanger
- St. John's Hospital, School of Medicine, Department of Cardiac Surgery, Salzburg, Austria.
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31
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Affiliation(s)
- Tommaso Gori
- Division of Cardiology, Department of Medicine, Mount Sinai and University Health Network Hospitals, University of Toronto, Toronto, Canada
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Affiliation(s)
- Tommaso Gori
- Division of Cardiology, Department of Medicine, Mount Sinai and University Health Network Hospitals, the University of Toronto, Toronto, Canada
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Affiliation(s)
- Adrian J Hobbs
- Wolfson Institute for Biomedical Research, University College London, Cruciform Building, Gower Street, London WC1E 6AE.
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Mumtaz F, Khan M, Mikhailidis D, Morgan R. RE: LONG-TERM EFFICACY OF SILDENAFIL AND TACHYPHYLAXIS EFFECT. J Urol 2002. [DOI: 10.1016/s0022-5347(05)64889-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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35
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RE: LONG-TERM EFFICACY OF SILDENAFIL AND TACHYPHYLAXIS EFFECT. J Urol 2002. [DOI: 10.1097/00005392-200207000-00073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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36
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Abstract
The role of nitric oxide (NO) in numerous physiologic systems only recently has been discovered. When used as a gas, inhaled NO (iNO) has many unique properties that cause immediate improvements in pulmonary hemodynamics and oxygenation. Acute benefits in physiologic parameters have been demonstrated in numerous studies of iNO in acute respiratory distress syndrome (ARDS), but recent randomized controlled trials have failed to show improvement in outcome. The addition of other treatments that prolong or enhance the affect of iNO or its use with other ventilator modalities such as prone positioning or high-frequency ventilation offer hope that iNO may be beneficial in select groups of patients.
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Affiliation(s)
- James R Klinger
- Division of Pulmonary, Sleep and Critical Care Medicine, Brown University School of Medicine, Rhode Island Hospital, Providence, Rhode Island, USA.
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Minamiyama Y, Imaoka S, Takemura S, Okada S, Inoue M, Funae Y. Escape from tolerance of organic nitrate by induction of cytochrome P450. Free Radic Biol Med 2001; 31:1498-508. [PMID: 11728822 DOI: 10.1016/s0891-5849(01)00733-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The mechanism of organic nitrate tolerance is poorly defined. We studied the rat P450-catalyzed conversion of organic nitrate to nitric oxide (NO) by purified P450 isoforms relationship between P450 expression and nitrate tolerance following continuous infusion of organic nitrates in rats. The hypotensive effect of an nitroglycerin (NTG) bolus injection was abolished in rats that had been previously provided a continuous 48 h infusion of NTG. This effect was accompanied by a gradual but marked decrease in plasma and urinary nitrate levels following a peak at 18-24 h. Nitrate tolerance was reversible; the decline in the hypotensive effect and P450 levels observed after 2 d of continuous infusion was followed by restoration to control levels 2 d after cessation of the infusion. Similarly, the hypotensive action disappeared in P450-depleted, and -inhibited rats. At 48 h after infusion, NTG-induced NO generation of the vessels increased in acetone (a P450 inducer) -pretreated rats. The appearance and disappearance of P450 paralleled the conversion of organic nitrates to NO. Our observations indicate that nitrate tolerance is in large part the result of decreased P450 expression and activity. Interventions that maintain or increase P450 activity may be a strategy to provide relief from ischemic conditions in humans.
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Affiliation(s)
- Y Minamiyama
- Department of Biochemistry and Molecular Pathology, Osaka City University Graduate School of Medicine, Osaka, Japan.
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38
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Kim D, Rybalkin SD, Pi X, Wang Y, Zhang C, Munzel T, Beavo JA, Berk BC, Yan C. Upregulation of phosphodiesterase 1A1 expression is associated with the development of nitrate tolerance. Circulation 2001; 104:2338-43. [PMID: 11696475 DOI: 10.1161/hc4401.098432] [Citation(s) in RCA: 141] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The efficacy of nitroglycerin (NTG) as a vasodilator is limited by tolerance, which develops shortly after treatment begins. In vascular smooth muscle cells (VSMCs), NTG is denitrated to form nitric oxide (NO), which activates guanylyl cyclase and generates cGMP. cGMP plays a key role in nitrate-induced vasodilation by reducing intracellular Ca(2+) concentration. Therefore, one possible mechanism for development of nitrate tolerance would be increased activity of the cGMP phosphodiesterase (PDE), which decreases cGMP levels. METHODS AND RESULTS To test this hypothesis, rats were made tolerant by continuous infusion of NTG for 3 days (10 microgram kg(-1). min(-1) SC) with an osmotic pump. Analysis of PDE activities showed an increased function of Ca(2+)/calmodulin (CaM)-stimulated PDE (PDE1A1), which preferentially hydrolyzes cGMP after NTG treatment. Western blot analysis for the Ca(2+)/CaM-stimulated PDE revealed that PDE1A1 was increased 2.3-fold in NTG-tolerant rat aortas. Increased PDE1A1 was due to mRNA upregulation as measured by relative quantitative reverse transcription-polymerase chain reaction. The PDE1-specific inhibitor vinpocetine partially restored the sensitivity of the tolerant vasculature to subsequent NTG exposure. In cultured rat aortic VSMCs, angiotensin II (Ang II) increased PDE1A1 activity, and vinpocetine blocked the effect of Ang II on decrease in cGMP accumulation. CONCLUSIONS Induction of PDE1A1 in nitrate-tolerant vessels may be one mechanism by which NO/cGMP-mediated vasodilation is desensitized and Ca(2+)-mediated vasoconstriction is supersensitized. Inhibiting PDE1A1 expression and/or activity could be a novel therapeutic approach to limit nitrate tolerance.
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MESH Headings
- 3',5'-Cyclic-GMP Phosphodiesterases/antagonists & inhibitors
- 3',5'-Cyclic-GMP Phosphodiesterases/genetics
- 3',5'-Cyclic-GMP Phosphodiesterases/metabolism
- Angiotensin II/pharmacology
- Animals
- Aorta/drug effects
- Aorta/enzymology
- Atrial Natriuretic Factor/pharmacology
- Cells, Cultured
- Cyclic GMP/metabolism
- Cyclic Nucleotide Phosphodiesterases, Type 1
- Cyclic Nucleotide Phosphodiesterases, Type 5
- Dose-Response Relationship, Drug
- Drug Tolerance
- Enzyme Induction/drug effects
- In Vitro Techniques
- Isoenzymes/genetics
- Isoenzymes/metabolism
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Nitric Oxide Donors/pharmacology
- Nitroglycerin/pharmacology
- Phosphodiesterase Inhibitors/pharmacology
- Phosphoric Diester Hydrolases/drug effects
- Phosphoric Diester Hydrolases/genetics
- Phosphoric Diester Hydrolases/metabolism
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Up-Regulation/drug effects
- Vasodilator Agents/pharmacology
- Vinca Alkaloids/pharmacology
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Affiliation(s)
- D Kim
- Department of Medicine, University of Rochester, Rochester, NY, USA
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39
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Wang EQ, Soda DM, Fung HL. Nitroglycerin-induced relaxation of anorectal smooth muscle: evidence for apparent lack of tolerance development in the anaesthetized rat. Br J Pharmacol 2001; 134:418-24. [PMID: 11564661 PMCID: PMC1572949 DOI: 10.1038/sj.bjp.0704239] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
1. Recent studies indicate that nitroglycerin (NTG) can produce beneficial clinical effects in healing anal fissures through the relaxation of the internal anal sphincter. The in vivo relaxation effects of NTG on the anorectal smooth muscle have not been studied and it is not known whether this tissue may also exhibit pharmacological tolerance toward NTG. 2. We have developed an in vivo procedure in the anaesthetized rat that permits continual monitoring of anorectal pressure after intravenous (i.v.) and intra-rectal application of NTG. The relaxant effects of NTG were quantified via the area-under-the-contraction-waveforms vs time curve (AUEC). 3. AUEC decreased significantly after intra-rectal bolus doses of NTG (5 - 25 microg), in a dose- and time-dependent manner. Sustained relaxation effects on anorectal pressure were also observed after continuous intra-rectal infusions of NTG. 4. Two-hours of i.v. NTG infusion led to a significant reduction in the mean arterial blood pressure (MAP) response toward a i.v. NTG (30 microg) bolus challenge. In contrast, relaxation of the anorectal pressure toward the challenge dose was not altered after NTG infusion. 5. In isolated tissues, cyclic GMP accumulation was significantly decreased after NTG pre-incubation in the rat aorta but not in the rat anorectal smooth muscle and anal sphincter. 6. These results indicate that the relaxation response toward NTG was not diminished in the anorectum under conditions that produced vascular tolerance. Thus, NTG causes significant and sustained in vivo relaxation of anorectal smooth muscle in the anaesthetized rat without evidence of tolerance development.
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Affiliation(s)
- Ellen Q Wang
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, SUNY, Buffalo, New York, NY 14260-1200, U.S.A
| | - David M Soda
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, SUNY, Buffalo, New York, NY 14260-1200, U.S.A
| | - Ho-Leung Fung
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, SUNY, Buffalo, New York, NY 14260-1200, U.S.A
- Author for correspondence:
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40
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Hussain MB, MacAllister RJ, Hobbs AJ. Reciprocal regulation of cGMP-mediated vasorelaxation by soluble and particulate guanylate cyclases. Am J Physiol Heart Circ Physiol 2001; 280:H1151-9. [PMID: 11179059 DOI: 10.1152/ajpheart.2001.280.3.h1151] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nitric oxide (NO) and atrial natriuretic peptides (ANP) activate soluble (sGC) and particulate guanylate cyclase (pGC), respectively, and play important roles in the maintenance of cardiovascular homeostasis. However, little is known about potential interactions between these two cGMP-generating pathways. Here we demonstrate that sGC and pGC cooperatively regulate cGMP-mediated relaxation in human and murine vascular tissue. In human vessels, the potency of spermine-NONOate (SPER-NO) and ANP was increased after inhibition of endogenous NO synthesis and decreased by prior exposure to glyceryl trinitrate (GTN). Aortas from endothelial NO synthase (eNOS) knockout (KO) mice were more sensitive to ANP than tissues from wild-type (WT) animals. However, in aortas from WT mice, the potency of ANP was increased after pretreatment with NOS or sGC inhibitor. Vessels from eNOS KO animals were less sensitive to ANP after GTN pretreatment, an effect that was reversed in the presence of an sGC inhibitor. cGMP production in response to SPER-NO and ANP was significantly greater in vessels from eNOS KO animals compared with WT animals. This cooperative interaction between NO and ANP may have important implications for human pathophysiologies involving deficiency in either mediator and the clinical use of nitrovasodilators.
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Affiliation(s)
- M B Hussain
- Centre for Clinical Pharmacology, The Rayne Institute, University College London, London WC1E 6JJ, United Kingdom
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41
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Abstract
OBJECTIVE To evaluate the efficacy of vitamin C in preventing the development of nitrate tolerance. DATA SOURCES A MEDLINE search (from 1966 to July 2000) was conducted to identify relevant articles, with additional references obtained from the bibliographies of these articles. DATA SYNTHESIS One possible mechanism of nitrate tolerance involves superoxide-induced deactivation of nitric oxide, providing the rationale for the use of antioxidants. Most published research concerning deactivation of nitric oxide has involved vitamin C; a summary of this information is presented here. CONCLUSIONS Preliminary studies seem to support the role of vitamin C in attenuating the development of nitrate tolerance. Considering these findings, larger, long-term trials are necessary to further establish the role of vitamin C in this situation.
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Affiliation(s)
- T A Daniel
- College of Pharmacy, University of New Mexico, Albuquerque 87131, USA
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42
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Christiansen I, Iversen HK, Olesen J. Headache characteristics during the development of tolerance to nitrates: pathophysiological implications. Cephalalgia 2000; 20:437-44. [PMID: 11037739 DOI: 10.1046/j.1468-2982.2000.00064.x] [Citation(s) in RCA: 24] [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
Recent studies suggest that nitric oxide (NO) plays an important role in nitrate-induced headache and in spontaneous migraine attacks. Organic nitrates act as prodrugs for NO and headache is a predominant adverse effect of nitrates but often disappears during continuous treatment. Insight into tolerance to headache could lead to insight into vascular headache mechanisms in general. The specific aim of the present study was therefore to characterize the headache and accompanying symptoms during continuous nitrate administration until a state of tolerance to headache had developed. 5-isosorbide-mononitrate (5-ISMN) 30 mg three times daily was administered orally for 7 days in 11 healthy subjects in a double-blind, randomized placebo controlled cross-over design. Wash-out between periods was 14 days or more. Haemodynamic data from the present study were compared to the observed changes of headache over time. Headache during 5-ISMN was longer lasting and more severe compared to placebo (P<0.004). In 10 subjects the headache fulfilled the pain sub-criteria for migraine and in five subjects all diagnostic criteria for migraine without aura were fulfilled. Conversely, 20 min of intravenous infusion of glyceryl trinitrate caused a milder headache and no migraine. The present results therefore suggest that NO may elicit a migraine attack in many healthy subjects if a high enough dose is given for several hours. A close temporal association between the disappearance of headache and the attenuation of the 5-ISMN induced dilatation of the superficial temporal artery was observed. In contrast, tolerance in the middle cerebral artery already appeared after 24 h, which was earlier than the development of tolerance to headache. If vasodilatation is the cause of headache the results point to extracerebral arteries. However, cytotoxic and pain modulating central nervous system effects of NO, the time courses of which are unknown, may also play a role, involving both intra- and extracranial arteries.
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Affiliation(s)
- I Christiansen
- Department of Neurology, Glostrup Hospital, University of Copenhagen, Glostrup, Denmark
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Lang D, Mosfer SI, Shakesby A, Donaldson F, Lewis MJ. Coronary microvascular endothelial cell redox state in left ventricular hypertrophy : the role of angiotensin II. Circ Res 2000; 86:463-9. [PMID: 10700452 DOI: 10.1161/01.res.86.4.463] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Left ventricular hypertrophy (LVH) is associated with elevated plasma angiotensin II (Ang II) levels and endothelial dysfunction. The relationship between Ang II and endothelial dysfunction remains unknown, however, but it may involve an alteration in endothelial cell redox state. We therefore investigated the effect of Ang II on NADH/NADPH oxidase-mediated superoxide anion (O(2)(-)) production by cultured guinea pig coronary microvascular endothelial cells (CMVEs) and CMVEs freshly isolated from a guinea pig, pressure-overload model of LVH. Lucigenin chemiluminescence was used to measure O(2)(-) production in the particulate fraction of CMVE lysates. In cultured cells, incubation with Ang II (0.1 nmol/L to 1 micromol/L for 18 hours) resulted in significant (P<0.01) increases in both NADH- and NADPH-dependent O(2)(-) production, with a peak effect at 1 nmol/L. The latter was significantly (P<0.01) inhibited by the AT(1) receptor antagonist losartan (1 micromol/L for 18 hours). In contrast, the O(2)(-) response to Ang II (0.1 nmol/L to 1 micromol/L for 18 hours) was largely unaffected by concomitant exposure to the AT(2) antagonist PD 123319 (1 micromol/L). In freshly isolated CMVEs from nonoperated animals, NADH- and NADPH-dependent O(2)(-) production was not different from that in sham-operated animals but was significantly (P<0.05) elevated in the aortic-banded animals. Plasma Ang II levels were significantly (P<0.001) elevated in the aortic-banded (1.25+/-0.12 microg/L, n=12) compared with sham-operated animals (0.63+/-0.06 microg/L, n=12). These data suggest that the endothelial dysfunction associated with LVH may be due, at least in part, to the Ang II-induced upregulation of NADH/NADPH oxidase-dependent O(2)(-) production.
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Affiliation(s)
- D Lang
- Cardiovascular Sciences Research Group, Sir Geraint Evans Wales Heart Research Institute, Department of Pharmacology, Therapeutics, and Toxicology, University of Wales College of Medicine, Cardiff, Wales.
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44
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Cabassi A, Bouchard JF, Dumont EC, Girouard H, Le Jossec M, Lamontagne D, Besner JG, de Champlain J. Effect of antioxidant treatments on nitrate tolerance development in normotensive and hypertensive rats. J Hypertens 2000; 18:187-96. [PMID: 10694187 DOI: 10.1097/00004872-200018020-00009] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVES To investigate the effect of chronic antioxidant treatments on the development of nitrate tolerance in spontaneously hypertensive (SHR) and normotensive Wistar-Kyoto (WKY) rats by evaluating (i) coronary vascular reactivity, (ii) lipid peroxidation (malondialdehyde), and (iii) peroxynitrite formation (3-nitrotyrosine). METHODS Tolerance was induced in 16-week-old male SHR and WKY, by 4 days of continuous treatment with nitroglycerin patches. Two groups were orally pre-treated (2-weeks) with antioxidants: N-acetyl-L-cysteine (NAC) or melatonin. Effects of serotonin (5-HT) and sodium nitroprusside (SNP) perfusion were tested in isolated Langendorff-perfused hearts. 3-Nitrotyrosine levels were measured in coronary sinus effluent and malondialdehyde in plasma. RESULTS Nitrate tolerance reduced SNP-induced dilation in both strains. This alteration was differently improved by antioxidants: melatonin was effective in SHR, whereas NAC was effective in WKY. Tolerance also reduced 5-HT-mediated vasodilation in WKY, which was reversed by both antioxidants. By contrast, nitrate tolerance enhanced the vasoconstriction to 5-HT in SHR and both antioxidants prevented this response. Furthermore, tolerance was associated with higher malondialdehyde levels in both strains and with higher 3-nitrotyrosine levels in SHR. These changes were reversed by both antioxidants. CONCLUSIONS A participation of oxidative stress was suggested during nitrate tolerance development, since antioxidants prevented the increase in lipid peroxidation and improved vascular responses to SNP and 5HT. Differential effects of antioxidants on SNP-induced vasodilation in SHR and WKY may suggest distinct mechanisms of tolerance development in hearts from hypertensive and normotensive rats. An increased peroxynitrite generation, expressed by higher 3-nitrotyrosine levels, could contribute to nitrate tolerance in the coronary circulation of SHR.
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Affiliation(s)
- A Cabassi
- Department of Physiology, Faculty of Medicine, University of Montreal, Québec, Canada
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45
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Kawazoe T, Kosaka H, Yoneyama H, Hata Y. Acute production of vascular superoxide by angiotensin II but not by catecholamines. J Hypertens 2000; 18:179-85. [PMID: 10694186 DOI: 10.1097/00004872-200018020-00008] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
OBJECTIVE To determine whether vascular superoxide is rapidly released by angiotensin II and is involved in vascular contraction. DESIGN The effect of superoxide dismutase (SOD) on angiotensin II induced elevation of mean arterial blood pressure was measured. Subsequently, acute production of vascular superoxide by angiotensin II and its effect on isometric tension were measured in rat aortic rings. The effects of catecholamines were concomitantly measured. METHODS AND RESULTS The acute pressor effects of angiotensin II were significantly reduced when rats were pretreated intravenously with SOD. When angiotensin II was added on aortic segments in the presence of Cypridina luciferin analog, immediate elevations of chemiluminescence were observed which were inhibited by SOD. Furthermore, angiotensin II-induced elevations of isometric tension in aortic rings were significantly reduced by SOD. The effects of epinephrine and norepinephrine were concomitantly measured and were not significant CONCLUSIONS The acute superoxide producing effect is likely to be specific to angiotensin II, because such a significant modification of the effects was not observed for catecholamines. Our results suggest that angiotensin II causes acute vascular superoxide production, which may be involved in the acute pressor effects.
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Affiliation(s)
- T Kawazoe
- Department of Plastic Surgery, Kagawa Medical University, Kita, Japan
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46
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Affiliation(s)
- Y Yeghiazarians
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
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47
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Haj-Yehia A, Nassar T, Lotan C, M�nzel T, Benet L, �ngg�rd EE. Development of 3-nitratomethyl-proxyl (NMP): A novel, bifunctional superoxide dismutase-mimic-nitric oxide-donor. Drug Dev Res 2000. [DOI: 10.1002/1098-2299(200007/08)50:3/4<528::aid-ddr36>3.0.co;2-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Kielbasa W, Fung HL. Relationship between pharmacokinetics and hemodynamic effects of inhaled isobutyl nitrite in conscious rats. AAPS PHARMSCI 2000; 2:E11. [PMID: 11741227 PMCID: PMC2751025 DOI: 10.1208/ps020211] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2000] [Accepted: 04/10/2000] [Indexed: 12/29/2022]
Abstract
Our objective was to examine the pharmacokinetic/hemodynamic properties of inhaled isobutyl nitrite (ISBN) in rats. ISBN is one of the volatile organic nitrites that has been used primarily as a drug of abuse. Recent studies indicate, however, that these compounds may be superior to organic nitrates for cardiovascular use because they do not produce vascular tolerance. Rats inhaled ISBN over an exposure range of 20 to 1200 ppm for 1 hour. The effects of ISBN on blood pressure and heart rate were determined and blood concentrations of ISBN were analyzed with use of gas chromatography. Apparent steady-state blood levels of ISBN were achieved during inhalation and were linear with exposure concentration (blood concentration: 0.05 to 3.5 microM; exposure concentration: 23 to 1177 ppm; r2= 0.92). Inhaled ISBN caused rapid, dose-dependent, and parallel reductions in systolic and diastolic pressure, while heart rate increased maximally to 22%. A sigmoid Emax model could describe the mean arterial pressure effect of inhaled ISBN (Emax= 55%; EC50= 0.51 microM). After inhalation, blood pressure and heart rate quickly returned to baseline, without any withdrawal rebound effect. Inhaled ISBN produced a rapid onset of action on heart rate and blood pressure, and these effects were sustained over 60 minutes of exposure. Abrupt drug withdrawal did not lead to hemodynamic rebound. The blood pressure effects were related to ISBN blood concentration by the sigmoid Emax model. These results provide new information on the pharmacokinetic/pharmacodynamic relationship of a representative nitrite inhalant.
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Affiliation(s)
- William Kielbasa
- Department of Pharmaceutics, School of Pharmacy, University at Buffalo, State University of New York, 14260 Buffalo, NY
| | - Ho-Leung Fung
- Department of Pharmaceutics, School of Pharmacy, University at Buffalo, State University of New York, 14260 Buffalo, NY
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Rich S, McLaughlin VV. The effects of chronic prostacyclin therapy on cardiac output and symptoms in primary pulmonary hypertension. J Am Coll Cardiol 1999; 34:1184-7. [PMID: 10520810 DOI: 10.1016/s0735-1097(99)00320-4] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVES This study evaluated the response to prostacyclin dose reduction in patients with primary pulmonary hypertension (PPH) who developed high cardiac outputs. BACKGROUND Patients on prostacyclin require chronic upward dose titration to overcome tolerance to the medication. No upper limit of effective dose has been described. METHODS We studied 12 patients with PPH treated with chronic prostacyclin therapy who presented in high cardiac output states. Each patient underwent prostacyclin dose reduction under hemodynamic guidance targeted to reduce the cardiac index to < or =4 liter/min/M2, unless rebound pulmonary hypertension occurred. Following dose reduction, patients were observed for changes in the effectiveness of the prostacyclin. RESULTS Patients were treated for 39 +/- 20 months, resulting in a 71% reduction in pulmonary vascular resistance compared to baseline. At the time of their most recent evaluation their cardiac outputs were increased to 10.1 +/- 2.3 liter/min. The patients underwent a 39% dose reduction (range 12% to 78%) resulting in a change of mean PAP from 45 to 46 mm Hg (p = NS), cardiac index from 7.4 +/- 1.4 to 4 +/- 0.74 liter/min/M2 (p = 0.01), and pulmonary vascular resistance from 3.7 +/- 1.7 to 4.7 +/- 1.5 units (p < 0.001). In no instance did rebound pulmonary hypertension occur. However, the patients all retained their clinical benefit without a return of tolerance. CONCLUSIONS Excessive prostacyclin in PPH can lead to a high cardiac output state, suggesting it has important positive inotropic effects. In this circumstance, reducing the dose can allow the cardiac output to return to normal without worsening the clinical state.
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Affiliation(s)
- S Rich
- Department of Medicine, Rush University Medical College, Chicago, Illinois, USA.
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Darius H. Role of nitrates for the therapy of coronary artery disease patients in the years beyond 2000. J Cardiovasc Pharmacol 1999; 34 Suppl 2:S15-20; discussion S29-31. [PMID: 10499556 DOI: 10.1097/00005344-199908002-00004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Vasodilator therapy with nitrates has been used for almost a century to bring relief to patients suffering from angina. The acute anti-ischemic effects of nitro-vasodilators for the treatment and prevention of anginal attacks is unquestioned. In addition, nitrates are administered in order to reduce symptomatic and silent ischemic episodes, in patients with proven coronary heart disease who exert ST segment alterations on Holter monitoring. The reduction in total ischemic burden may result in an improved prognosis with regard to infarct prevention and possible prevention of deterioration of left ventricular function due to repetitive episodes of myocardial ischemia. In patients with unstable angina, administration of nitrates significantly diminishes ischemic episodes and reduces the number of clinically symptomatic anginal attacks. The prevention of left ventricular dilatation in patients within the first few days and months following acute myocardial infarction may be due to the reduced preload. In patients with heart failure, preload reduction with nitrates and afterload reduction with hydralazine was tested versus angiotensin converting enzyme (ACE) inhibitors. However, unfortunately, very few data are available concerning the combination therapy of ACE inhibitors and nitrates in heart failure and following acute myocardial infarction. Long-term continuous administration of high doses of nitrates may cause nitrate tolerance, thus reducing the vasodilator potency of these drugs. Since nitrates were introduced into medical therapy many decades before randomized controlled trials were performed, and evidence-based medicine became the basic principal for medical therapy, there are still indications and situations where the full therapeutic potential of nitrates is not being fully appreciated. During recent decades, other anti-ischemic drugs, i.e., beta-receptor agonists and calcium channel blockers, were introduced into the clinical setting and contributed to an optimized therapy for patients with coronary heart disease. Nevertheless, due to their proven and unsurmounted symptomatic efficacy, nitrates will remain one of the cornerstones of acute and long-term therapy of patients with coronary heart disease far beyond the year 2000.
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Affiliation(s)
- H Darius
- Department of Medicine II, Johannes Gutenberg University, Mainz, Germany.
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