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Kant S, Xing H, Liu Y, Harrington EO, Sellke FW, Feng J. Acute protein kinase C beta inhibition preserves coronary endothelial function after cardioplegic hypoxia/reoxygenation. JTCVS OPEN 2023; 15:242-251. [PMID: 37808045 PMCID: PMC10556935 DOI: 10.1016/j.xjon.2023.06.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 06/18/2023] [Accepted: 06/27/2023] [Indexed: 10/10/2023]
Abstract
Objective Protein kinase C (PKC) influences myocardial contractility and susceptibility to long-term cardiac dysfunction after ischemia-reperfusion injury. In diabetes, PKC inhibition has a protective effect in terms of microvascular dysfunction. SK-channel dysfunction also influences endothelial dysfunction in cardioplegic hypoxia-reoxygenation (CP-H/R). Here, we examine whether acute inhibition of PKC beta protects against CP-H/R-induced coronary endothelial and SK channel dysfunction. Methods Isolated mouse coronary arterioles, half pretreated with selective PKC inhibitor ruboxistaurin (RBX), were subjected to hyperkalemic, cardioplegic hypoxia (1 hour), and reoxygenation (1 hour) with Krebs buffer. Sham control vessels were continuously perfused with oxygenated Krebs buffer without CP-H/R. After 1 hour of reoxygenation, responses to the endothelium-dependent vasodilator adenosine-diphosphate (ADP) and the SK-channel activator NS309 were examined. Endothelial SK-specific potassium currents from mouse heart endothelial cells were examined using whole-cell path clamp configurations in response to NS309 and SK channel blockers apamin and TRAM34. Results CP-H/R significantly decreased coronary relaxation responses to ADP (P = .006) and NS309 (P = .0001) compared with the sham control group. Treatment with selective PKC beta inhibitor RBX significantly increased recovery of coronary relaxation responses to ADP (P = .031) and NS309 (P = .004) after CP-H/R. Treatment with RBX significantly increased NS309-mediated potassium currents following CP-H/R (P = .0415). Apamin and TRAM34 sensitive currents were significantly greater in CP-H/R + RBX versus CP-H/R mouse heart endothelial cells (P = .0027). Conclusions Acute inhibition of PKC beta significantly protected mouse coronary endothelial function after CP-H/R injury. This suggests that acute PKC beta inhibition may be a novel approach for preventing microvascular dysfunction during CP-H/R.
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Affiliation(s)
- Shawn Kant
- Division of Cardiothoracic Surgery, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI
| | - Hang Xing
- Division of Cardiothoracic Surgery, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI
| | - Yuhong Liu
- Division of Cardiothoracic Surgery, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI
| | - Elizabeth O. Harrington
- Vascular Research Laboratory, Department of Medicine, Providence VA Medical Center, Alpert Medical School of Brown University, Providence, RI
| | - Frank W. Sellke
- Division of Cardiothoracic Surgery, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI
| | - Jun Feng
- Division of Cardiothoracic Surgery, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI
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Clinical Significance of Serum Nitric Oxide, Urine Nitric Oxide, and Urinary Nitric Oxide-to-Creatinine Ratio in Acute Pancreatitis. Indian J Surg 2022. [DOI: 10.1007/s12262-022-03580-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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3
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Choudhury M, Hote M, Kapoor PM, Saini S, Kiran U. Does Preoperative Plasma Endothelin-1 Level Influences the Postoperative Events in Patients Undergoing Coronary Artery Bypass Grafting (CABG)? Revisiting Endothelin-1 Molecule in CABG Patients. JOURNAL OF CARDIAC CRITICAL CARE TSS 2022. [DOI: 10.1055/s-0042-1757362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
Abstract
AbstractEndothelin-1 (ET-1) is a powerful physiological vasoconstrictor release in response to endothelial injury. Increased synthesis of endothelin is associated with myocardial ischemia and reperfusion injury. The normal level varies between 0.2 and 18.5 pg/mL that maintains normal vascular homeostasis. We hypothesized that there exists a correlation between ET-1 and clinical outcome in patient undergoing elective coronary artery bypass grafting (CABG) surgery under cardiopulmonary bypass.Fifty-eight patients undergoing elective on-pump CABG were enrolled in the study. Blood sample for plasma ET-1 was taken before anesthesia induction. The median ET-1 level was 5 pg/mL (range: 0.6–30.33 pg/mL). The inotropic and intraaortic balloon pump requirement was significantly higher among patients having baseline ET-1 level more than 14.24pg/mL (p = 0.001in each case). A similar finding was observed in the duration of mechanical ventilation, intensive care unit stay, and duration of hospital stay (r = 0.68, p = 0.000; r = 0.58, p = 0.000; and r = 0.61, p = 0.000 respectively). The occurrence of complications was also more in individuals with higher baseline ET-1 level. The p-value was significant for occurrence infection, arrhythmia, renal and respiratory problems as observed in postoperative period by using Mann–Whitney U test.This study concludes that higher level of preoperative ET-1 levels correlates well to adverse clinical outcome in patients undergoing on-pump CABG surgery, so herein it can be used as a single independent parameter to predict postoperative outcome.
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Affiliation(s)
- Minati Choudhury
- Department of Cardiac Anaesthesia and Critical Care, All India Institute of Medical Sciences, New Delhi, India
| | - Milind Hote
- Department of Cardiothoracic and Vascular Surgery, All India Institute of Medical Sciences, New Delhi, India
| | - Poonam Malhotra Kapoor
- Department of Cardiac Anaesthesia and Critical Care, All India Institute of Medical Sciences, New Delhi, India
| | - Savita Saini
- Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India
| | - Usha Kiran
- Department of Cardiac Anaesthesia and Critical Care, All India Institute of Medical Sciences, New Delhi, India
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4
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Jaghoori A, Lamin V, Jacobczak R, Worthington M, Edwards J, Viana F, Stuklis R, Wilson DP, Beltrame JF. Sex differences in vascular reactivity of coronary artery bypass graft conduits. Heart Vessels 2020; 35:422-431. [PMID: 31576420 DOI: 10.1007/s00380-019-01508-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Accepted: 09/20/2019] [Indexed: 11/29/2022]
Abstract
Females have increase in-hospital mortality and poorer outcomes following coronary artery bypass grafting (CABG). Biological differences in the reactivity of the graft conduits to circulating catecholamine may contribute to this sex difference. This study examined sex differences in the vasoconstrictor responses of internal mammary artery (IMA) and saphenous vein (SV) conduits to phenylephrine (PE) and endothelin-1 (ET-1). Functional IMA and SV were obtained from 78 male and 50 female patients undergoing CABG (67.7 ± 11 and 69 ± 10 years, respectively) and subjected to the following experimental conditions. (1) Concentration response curves for PE and ET-1 were generated in an intact IMA and SV and endothelium denuded IMA segments, (2) in the presence of the nitric oxide synthase inhibitor (L-NAME) or the cyclooxygenase inhibitor (indomethacin) in an endothelium-intact IMA and (3) the activity state (abundance and phosphorylation) of the α1-adrenergic receptor was investigated using Phos-tag™ western blot analysis. (1) Compared to male, female IMA and SV were hypersensitive to PE but not ET-1 (p < 0.05). The female IMA hypersensitivity response to PE was abolished following endothelial denudation, (2) persisted in the presence of L-NAME but was abolished in the presence of indomethacin and (3) there was no sex differences in the abundance and phosphorylation of the α1-adrenergic receptor in IMA. Female IMA and SV graft conduits are hypersensitive to α1-adrenergic stimuli. This endothelial cyclooxygenase pathway-mediated hypersensitivity may produce excessive IMA and SV graft constriction in females administered catecholamines and could contribute to their poorer CABG outcomes.
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Affiliation(s)
- Amenah Jaghoori
- Discipline of Medicine, Adelaide Medical School, University of Adelaide, Adelaide, Australia
- Cardiology Unit, Basil Hetzel Institute for Translational Health Research, The Queen Elizabeth Hospital, Central Adelaide Local Health Network, 28 Woodville Road, Woodville, SA, 5011, Australia
| | - Victor Lamin
- Discipline of Medicine, Adelaide Medical School, University of Adelaide, Adelaide, Australia
- Cardiology Unit, Basil Hetzel Institute for Translational Health Research, The Queen Elizabeth Hospital, Central Adelaide Local Health Network, 28 Woodville Road, Woodville, SA, 5011, Australia
| | - Rachel Jacobczak
- Discipline of Medicine, Adelaide Medical School, University of Adelaide, Adelaide, Australia
| | - Michael Worthington
- D'Arcy Sutherland Cardiothoracic Surgical Unit, Royal Adelaide Hospital, Central Adelaide Local Health Network, 1 Port Road, Adelaide, 5000, Australia
| | - James Edwards
- D'Arcy Sutherland Cardiothoracic Surgical Unit, Royal Adelaide Hospital, Central Adelaide Local Health Network, 1 Port Road, Adelaide, 5000, Australia
| | - Fabiano Viana
- D'Arcy Sutherland Cardiothoracic Surgical Unit, Royal Adelaide Hospital, Central Adelaide Local Health Network, 1 Port Road, Adelaide, 5000, Australia
| | - Robert Stuklis
- D'Arcy Sutherland Cardiothoracic Surgical Unit, Royal Adelaide Hospital, Central Adelaide Local Health Network, 1 Port Road, Adelaide, 5000, Australia
| | - David P Wilson
- Discipline of Medicine, Adelaide Medical School, University of Adelaide, Adelaide, Australia
- Cardiology Unit, Basil Hetzel Institute for Translational Health Research, The Queen Elizabeth Hospital, Central Adelaide Local Health Network, 28 Woodville Road, Woodville, SA, 5011, Australia
| | - John F Beltrame
- Discipline of Medicine, Adelaide Medical School, University of Adelaide, Adelaide, Australia.
- Cardiology Unit, Basil Hetzel Institute for Translational Health Research, The Queen Elizabeth Hospital, Central Adelaide Local Health Network, 28 Woodville Road, Woodville, SA, 5011, Australia.
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Optimal Conduit for Diabetic Patients: Propensity Analysis of Radial and Right Internal Thoracic Arteries. Ann Thorac Surg 2014; 98:30-6; discussion 36-7. [DOI: 10.1016/j.athoracsur.2014.03.044] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 03/18/2014] [Accepted: 03/26/2014] [Indexed: 11/23/2022]
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Ferrario CM, Jessup JA, Smith RD. Hemodynamic and hormonal patterns of untreated essential hypertension in men and women. Ther Adv Cardiovasc Dis 2013; 7:293-305. [PMID: 24280597 DOI: 10.1177/1753944713513221] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Knowledge of hemodynamic factors accounting for the development of hypertension should help to tailor therapeutic approaches and improve blood pressure control. Few data exist regarding sex differences of hemodynamic factors contributing to hypertension progression among patients with untreated nondiabetic stage I and II prehypertension (PreHyp) as defined by the Joint National Committee-7 guidelines (JNC-7). METHODS We utilized noninvasive impedance cardiography, applanation tonometry and plasma measures of angiotensin II, angiotensin (1-7), serum aldosterone, high-sensitivity C-reactive protein (hs-CRP) and cytokine biomarkers of inflammation to characterize the hemodynamic and hormonal profile of 100 patients with untreated hypertension (39 women). RESULTS Despite there being no differences between women and men in terms of office blood pressure, heart rate and body mass index, men demonstrated lower values of pulse pressure, systemic vascular resistance, brachial artery pulse wave velocity and augmentation index. In each of the three hypertension categories, the increased blood pressure in men was associated with significant augmentations in stroke volume and cardiac output compared with women. Sex-related hemodynamic differences were associated in women with higher plasma levels of leptin, hs-CRP, plasma angiotensin II and serum aldosterone, and no differences in the serum concentrations of cytokinins. In women but not men, hs-CRP correlated with plasma concentrations of transforming growth factor β1 (TGFβ1) and body weight; in addition, plasma TGFβ1 correlated with levels of serum vascular cell adhesion molecule 1. CONCLUSION The impact of sex differences in the hemodynamic factors accounting for the elevation in arterial pressure in subjects with essential hypertension has been poorly characterized or this information is not available. We suggest that this gap in knowledge may adversely influence choices of drug treatment since our study shows for the first time significant differences in the hemodynamic and hormonal mechanisms accounting for the increased blood pressure in women compared to men.
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Affiliation(s)
- Carlos M Ferrario
- Laboratory of Translational Hypertension Research, Department of Surgery, Wake Forest University School of Medicine, Winston Salem, NC 27157, USA
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Lin J, Cheng W, Czer LS, De Robertis MA, Mirocha J, Ruzza A, Kass RM, Khoynezhad A, Ramzy D, Esmailian F, Trento A. Coronary artery bypass graft surgery using the radial artery as a secondary conduit improves patient survival. J Am Heart Assoc 2013; 2:e000266. [PMID: 23969224 PMCID: PMC3828817 DOI: 10.1161/jaha.113.000266] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The clinical benefits of the left internal thoracic artery-to-left anterior descending coronary artery graft are well established in coronary artery bypass graft surgery (CABG). However, limited data are available regarding the long-term outcome of the radial artery (RA) as a secondary conduit over the established standard of the saphenous venous graft. METHODS AND RESULTS We compared the 12-year survival outcome in a set of propensity-matched CABG patients who received either the RA or the saphenous vein as a secondary conduit. A multivariable logistic regression that included 18 baseline characteristics was used to define the propensity of receiving an RA graft. The propensity model resulted in 260 matched pairs who underwent first-time isolated CABG from 1996 to 2001 with similar preoperative characteristics (C statistic=0.86). The cumulative 12-year survival estimated by use of the Kaplan-Meier method was higher for the RA graft patients (hazard ratio 0.76; P=0.03). This survival advantage was especially significant in diabetics (P=0.005), in women (P=0.02), and in the elderly (P=0.04.) The protective effect appeared beginning at year 5 post surgical intervention. CONCLUSION The RA as a secondary conduit provided superior long-term survival after CABG, especially in diabetic patients, women, and the elderly. This effect was most pronounced >5 years after surgery.
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Affiliation(s)
- John Lin
- Division of Cardiothoracic Surgery, Cedars Sinai Heart Institute, Los Angeles, CA
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Schwann TA, Al-Shaar L, Engoren M, Habib RH. Late effects of radial artery vs saphenous vein grafting for multivessel coronary bypass surgery in diabetics: a propensity-matched analysis. Eur J Cardiothorac Surg 2013; 44:701-10. [PMID: 23428573 DOI: 10.1093/ejcts/ezt061] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES To determine whether the use of the radial artery (RA) vs the saphenous vein (SV) as the second grafting conduit with the internal thoracic artery (ITA) confers a late-survival advantage in diabetes mellitus (DM). METHODS We reviewed our 1996-2007 DM coronary artery bypass grafting (CABG) experience. Study patients (N = 2281) included all primary, non-salvage multigraft CABG discharged alive and receiving ≥1 ITA graft. Bilateral ITA, ITA-only grafts or concomitant valve/aortic surgery patients were excluded. A non-parsimonious, RA use propensity model (42 variables) was derived excluding five factors [gender, vessel disease, insulin, renal failure and left ventricular (LV) dysfunction] that were always strictly matched for all pairs. Greedy matching resulted in well-matched ITA/RA and ITA/SV cohorts (N = 578 each). The late follow-up was truncated at 16 years, and survival comparisons were done by Kaplan-Meier analysis. RESULTS RA grafting was used in 933 (41%) DM patients and was more frequent for non-insulin (513/1348; 49.1%) compared with insulin (271/784; 34.6%) dependent patients. Relatively fewer insulin ITA/RA (169; 62%) could be matched vs non-insulin (469; 71%). Late survival was significantly better for ITA/RA overall [hazard ratio, HR (95% confidence interval) = 0.78 (0.65-0.95); P = 0.012], but this was primarily due to the non-insulin sub-cohort [HR = 0.72 (0.56-0.91); P = 0.007] as opposed to no effect for insulin [HR = 0.92 (0.68-1.26); P = 0.61]. Sub-cohort analysis revealed a significant ITA/RA survival advantage in males, preserved LV function and three-vessel disease. No sub-cohorts were associated with superior ITA/SV survival. CONCLUSION Our analysis indicated that RA grafting confers a significant late-survival advantage and, thus, supports its liberal use in DM patients undergoing multivessel CABG.
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Affiliation(s)
- Thomas A Schwann
- Department of Surgery, University of Toledo, College of Medicine, Toledo, OH, USA
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Chen H, Brahmbhatt S, Gupta A, Sharma AC. Duration of streptozotocin-induced diabetes differentially affects p38-mitogen-activated protein kinase (MAPK) phosphorylation in renal and vascular dysfunction. Cardiovasc Diabetol 2005; 4:3. [PMID: 15748291 PMCID: PMC555576 DOI: 10.1186/1475-2840-4-3] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2004] [Accepted: 03/05/2005] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In the present study we tested the hypothesis that progression of streptozotocin (STZ)-induced diabetes (14-days to 28-days) would produce renal and vascular dysfunction that correlate with altered p38- mitogen-activated protein kinase (p38-MAPK) phosphorylation in kidneys and thoracic aorta. METHODS Male Sprague Dawley rats (350-400 g) were randomized into three groups: sham (N = 6), 14-days diabetic (N = 6) and 28-days diabetic rats (N = 6). Diabetes was induced using a single tail vein injection of STZ (60 mg/kg, I.V.) on the first day. Rats were monitored for 28 days and food, water intake and plasma glucose levels were noted. At both 14-days and 28-days post diabetes blood samples were collected and kidney cortex, medulla and aorta were harvested from each rat. RESULTS The diabetic rats lost body weight at both 14-days (-10%) and 28-days (-13%) more significantly as compared to sham (+10%) group. Glucose levels were significantly elevated in the diabetic rats at both 14-days and 28-days post-STZ administration. Renal dysfunction as evidenced by renal hypertrophy, increased plasma creatinine concentration and reduced renal blood flow was observed in 14-days and 28-days diabetes. Vascular dysfunction as evidenced by decreased carotid blood flow was observed in 14-days and 28-days diabetes. We observed an up-regulation of inducible nitric oxide synthase (iNOS), prepro endothelin-1 (preproET-1) and phosphorylated p38-MAPK in thoracic aorta and kidney cortex but not in kidney medulla in 28-days diabetes group. CONCLUSION The study provides evidence that diabetes produces vascular and renal dysfunction with a profound effect on signaling mechanisms at later stage of diabetes.
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Affiliation(s)
- Hongmei Chen
- Cardionome Laboratory, Department of Pharmaceutical Sciences, College of Pharmacy North Dakota State University, Fargo, ND 58105, USA
| | - Sachin Brahmbhatt
- Cardionome Laboratory, Department of Pharmaceutical Sciences, College of Pharmacy North Dakota State University, Fargo, ND 58105, USA
| | - Akanksha Gupta
- Cardionome Laboratory, Department of Pharmaceutical Sciences, College of Pharmacy North Dakota State University, Fargo, ND 58105, USA
| | - Avadhesh C Sharma
- Cardionome Laboratory, Department of Pharmaceutical Sciences, College of Pharmacy North Dakota State University, Fargo, ND 58105, USA
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Donnini D, Del Terra E, Ambesi-Impiombato FS, Curcio F. New in vitro model to study high glucose-dependent endothelial dysfunctions. Biochimie 2004; 85:701-5. [PMID: 14505826 DOI: 10.1016/s0300-9084(03)00116-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Several thrombogenic abnormalities are associated with diabetes. Since endothelial dysfunction occurs at early stages of disease, it may reflect pathophysiological changes that are responsible for alterations in vascular structure, growth and modifications of adhesivity to platelets and leukocytes, leading to atherosclerosis and thrombosis. Predisposing factors of vascular diseases, such as diabetes, are also associated with endothelial dysfunction. Restoration or replacement of endothelium-related factors like nitric oxide impede the progression of vascular thrombogenic diseases, and prevent the action of vasoconstrictor factors such as endothelin or other prothrombotic factors such as plasminogen-activator inhibitor-1. Since high glucose concentration in blood is the hallmark of diabetes and because the vascular lesions of atherosclerosis are localized in large artheries, we have cultured endothelial cells from the human aorta. Two endothelial cell strains from the same aortic tract that show different characteristics and behavior in high glucose were isolated. Such findings reflect the importance to have well characterized and standardized cell culture systems to carry out experiments to study the glucose-dependent atherosclerotic process in vitro. Our cell strains may represent a useful in vitro model to study the complex pathophysiology of diabetes-related atherosclerosis.
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Affiliation(s)
- Debora Donnini
- Dipartimento di Patologia e Medicina Sperimentale e Clinica, Universita' degli Studi di Udine, P.le S.Maria della Misericordia, 33100, Udine, Italy.
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Sharma AC, Singh G, Gulati A. Decompensation characterized by decreased perfusion of the heart and brain during hemorrhagic shock: role of endothelin-1. THE JOURNAL OF TRAUMA 2002; 53:531-6. [PMID: 12352492 DOI: 10.1097/00005373-200209000-00022] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Endothelin-1 (ET-1), a 21-amino-acid peptide produced by vascular endothelium, is a potent vasoconstrictor and a component of local regulation of vascular tone through its effect on underlying vascular smooth muscle. Hemorrhagic shock (HS) is characterized by compensatory regional vasoconstriction to decrease peripheral tissue perfusion and to maintain core organ perfusion. Decompensation occurs with prolonged duration of HS. In the present study, we hypothesized that systemic and vital organ tissue ET-1 concentrations would correlate with changes in systemic and vital organ perfusion associated with compensatory and decompensatory states of HS. METHODS After surgical instrumentation, HS was induced in male Sprague-Dawley rats by withdrawing blood via femoral artery to a mean arterial pressure of 35 to 40 mm Hg that was maintained for either 30 minutes or 90 minutes in separate groups of male Sprague-Dawley rats. Systemic hemodynamics and regional blood flow were measured using a radioactive microsphere technique. In separate groups of animals, sham, 30 minutes of HS, or 90 minutes of HS, plasma and tissue concentrations of ET-1 were determined using a radioimmunoassay technique. RESULTS HS maintained for 90 minutes was associated with increased arterial base deficit from 3.6 +/- 0.53 mEq/L to 13 +/- 0.37 mEq/L, decreased cardiac output from 79 +/- 18 mL/min to 18 +/- 5 mL/min, and increased systemic vascular resistance from 1,004 +/- 102 mm Hg/L. min to 2,392 +/- 447 mm. Hg/L min as compared with baseline values. With 90 minutes of HS as compared with 30 minutes of HS, perfusion was significantly decreased in brain (72 +/- 11 vs. 29 +/- 6 mL/min. 100 g tissue) and heart (483 +/- 30 vs. 173 +/- 38 mL/min. 100 g tissue) and kidney perfusion was decreased (from 114 +/- 28 mL/min/100 g tissue to 29 +/- 2 mL/min. 100 g tissue), and ET-1 concentration was increased significantly in brain (cerebral cortex, 89 +/- 14 pg/100 g tissue to 144 +/- 19 pg/100 g tissue; midbrain, 172 +/- 15 pg/100 g tissue to 211 +/- 10 pg/100 g tissue), heart (left ventricle, 312 +/- 11 pg/100 g tissue to 360 +/- 14 pg/100 g tissue), kidney (medulla, 857 +/- 61 pg/100 g tissue to 1,277 +/- 41 pg/100 g tissue), and plasma (5.31 +/- 0.6 pg/100 g tissue to 21.26 +/- 2.9 pg/mL). CONCLUSION Decreased vital organ and peripheral tissue perfusion, a primary decompensation effect of HS, was apparent with 90 minutes of HS but not with 30 minutes, and was associated with increased vital organ tissue and plasma ET-1 concentrations. These data suggest a role for ET-1 in control mechanisms of progressive vasoconstriction that occurs with prolonged duration of HS.
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Affiliation(s)
- Avadhesh C Sharma
- Department of Pharmaceutics and Pharmacodynamics, University of Illinois at Chicago, College of Pharmacy, USA.
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Lockowandt U, Franco-Cereceda A. Is there a role for endothelin-blockade early after coronary artery bypass grafting? Ann Thorac Surg 2002; 74:727-32. [PMID: 12238831 DOI: 10.1016/s0003-4975(02)03709-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND Diverse results exist regarding myocardial release of endothelin after coronary artery bypass grafting. Because endothelin may be involved in regulation of coronary blood flow, postoperative endothelin-blockade could influence the surgical outcome. In this study, we have evaluated the cardiac outflow of endothelin and effects on coronary flow by endothelin-blockade immediately after completion of the coronary bypass grafting. METHODS Thirty patients were subjected to infusions of endothelinA blocker (BQ-123, 260 nmoL/min for up to 30 minutes) or endothelinA blocker and endothelinB blocker (BQ-123 and BQ-788, 260 and 250 nmol/min, respectively, for up to 30 minutes) into a veingraft anastomosed to a coronary vessel, and the coronary blood flow was measured. Plasma levels of endothelin from the coronary sinus and the periphery were determined. RESULTS There were no significant changes in flow caused by endothelinA blockade alone or in combination with endothelinB blockade. There were no immediately increased levels of endothelin after surgery or after infusions of the endothelin blockers. CONCLUSIONS Endothelin blockade does not influence the immediate perioperative myocardial blood flow after coronary bypass grafting. There is no significantly increased myocardial outflow of endothelin, and endothelin does not have any influence on the basal tone of the coronary vessels in the early phase after coronary bypass grafting.
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Affiliation(s)
- Ulf Lockowandt
- Department of Thoracic Surgery, Karolinska Hospital, Stockholm, Sweden.
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Verma S, Maitland A, Weisel RD, Fedak PWM, Li SH, Mickle DAG, Li RK, Ko L, Rao V. Increased endothelin-1 production in diabetic patients after cardioplegic arrest and reperfusion impairs coronary vascular reactivity: reversal by means of endothelin antagonism. J Thorac Cardiovasc Surg 2002; 123:1114-9. [PMID: 12063457 DOI: 10.1067/mtc.2002.121972] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVES Evidence has accrued to suggest that diabetic patients face an increased risk of ischemic events and low output syndrome and might mount an inordinate response to ischemia and reperfusion. Because hyperglycemia is a potent stimulus for endothelin-1 production, we hypothesized that increased production, action, or both of endothelin-1 in diabetes might represent an important mediator of endothelial dysfunction in patients with that disease. To this aim, we compared the effects of cardioplegic arrest and reperfusion on coronary sinus effluent endothelin-1 levels and atrial arteriolar vascular responses in diabetic and case-matched nondiabetic patients undergoing coronary artery bypass grafting. METHODS In study 1 coronary sinus effluent endothelin-1 levels were assessed at baseline and at 1 and 10 minutes after reperfusion in 13 diabetic and 12 nondiabetic patients matched for age, ejection fraction, Parsonnet score, and crossclamp time. In study 2 vascular responses of atrial arterioles subjected to perioperative ischemia-reperfusion were evaluated with videomicroscopy. Atrial microvessels (from appendages) were obtained before and after removal of the aortic crossclamp, and vascular responses to exogenously administered endothelin-1 (10(-10) mol/L) and substance P (10(-8) mol/L) were studied in the presence or absence of BQ-123, an endothelin A receptor antagonist. RESULTS Diabetic patients elaborated more endothelin-1 at 1 and 10 minutes after reperfusion (P =.01). Endothelin-1-mediated vasoconstriction was similar in diabetic and nondiabetic atrial microvessels before cardioplegic arrest and cardiopulmonary bypass. After cardiopulmonary bypass and reperfusion, endothelin-1-mediated vasoconstriction was enhanced in both groups; however, this response was greater in microvessels from diabetic patients (P =.02). BQ-123, the endothelin A antagonist, attenuated the effects of bypass and reperfusion on endothelin-1-mediated vasoconstriction in both groups (P =.01). Substance P-mediated vasodilatation was similar in diabetic and nondiabetic atrial microvessels before bypass. After bypass and reperfusion, substance P-mediated vasodilatation was diminished in both groups; however, this response was more pronounced in the diabetic group (P =.003). BQ-123 coincubation restored substance P-mediated vasodilatation in both groups. CONCLUSIONS We determined the following: (1) the coronary effluent release of endothelin-1 is higher in diabetic than in nondiabetic patients after cardiopulmonary bypass and reperfusion; (2) diabetic coronary microvessels respond to bypass and reperfusion with greater endothelin-1-mediated vasoconstriction and diminished nitric oxide-mediated vasodilatation; and (3) these effects are attenuated by endothelin antagonism. Endothelin-1 might be an important mediator of ischemia-reperfusion injury in patients with diabetes. Furthermore, use of endothelin receptor antagonists might be a novel strategy for improving the resistance of the diabetic heart to cardioplegic arrest and reperfusion.
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Affiliation(s)
- Subodh Verma
- Division of Cardiac Surgery, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada
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14
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Crittenden MD. Intraoperative metabolic monitoring of the heart: I. Clinical assessment of coronary sinus metabolites. Ann Thorac Surg 2001; 72:S2220-6; discussion S2267-70. [PMID: 11789845 DOI: 10.1016/s0003-4975(01)03296-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Numerous clinical studies have corroborated the ability of intraoperative sampling of coronary sinus blood to measure changes in myocardial metabolism induced by ischemia and reperfusion. Among other changes, cardiac arrest induces a period of obligate myocardial lactate production that persists for an indeterminate amount of time after reperfusion. Coronary sinus lactate assays have been established as a standard method to compare various myocardial protection strategies. Current methodology requires detailed sample processing, precluding real-time feedback in the operating room. Newer devices hold promise in allowing the online assessment of myocardial metabolism; however, these methods await precise validation.
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Affiliation(s)
- M D Crittenden
- Department of Surgery, VA Boston Healthcare System, Brigham and Women's Hospital, Harvard Medical School, Massachusetts, USA.
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Abstract
The metabolism of nitric oxide (NO) during cardiac surgery is unclear. We studied the effect of diabetes on NO metabolism during cardiac surgery in 40 subjects (20 with diabetes and 20 without diabetes). The patients were randomized to receive an infusion of physiological saline or nitroglycerin (GTN) at 1 microg. kg(-1). min(-1) starting 10 min before the initiation of cardiopulmonary bypass and then continuing for a period of 4 h. Blood and urine samples were collected at several time points for up to 8 h. NO metabolites were determined by the measurement of nitrate/nitrite (NOx, micromol/mmol creatinine) and cyclic guanosine monophosphate (cGMP, nmol/mmol creatinine) in plasma and urine. Plasma insulin levels were also determined at selected time points. Plasma NOx levels before surgery were significantly elevated in the group with diabetes compared with the group without diabetes (P < 0.001), and values were further increased during surgery in the former (P = 0.005) but not in the latter (P = 0.8). The greater plasma NOx values in patients with diabetes were matched by commensurate elevations in plasma cGMP levels (P = 0.01). Interestingly, infusion of GTN, an NO donor, significantly reduced plasma NOx (P < 0.001) and its urine elimination (P < 0.001) in patients with diabetes without reducing plasma cGMP levels (P = 0.89). Cardiac surgery increased plasma insulin in patients with and without diabetes; this increase was delayed by the infusion of GTN, but it was not related to the changes in NO production. In conclusion, NO production during cardiac surgery is increased in patients with diabetes, and this elevation can be blunted by the infusion of GTN in a rapid and reversible manner.
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Affiliation(s)
- B M Matata
- Division of Cardiac Surgery, Department of Surgery, University of Leicester, Glenfield Hospital, Leicester, United Kingdom
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