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Bessada SM, Alves RC, Oliveira MBP. Caffeine-based food supplements and beverages: Trends of consumption for performance purposes and safety concerns. Food Res Int 2018; 109:310-319. [DOI: 10.1016/j.foodres.2018.04.050] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 04/20/2018] [Accepted: 04/22/2018] [Indexed: 01/12/2023]
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El Messaoudi S, Wouters CW, van Swieten HA, Pickkers P, Noyez L, Kievit PC, Abbink EJ, Rasing-Hoogveld A, Bouw TP, Peters JG, Coenen MJH, Donders ART, Riksen NP, Rongen GA. Effect of dipyridamole on myocardial reperfusion injury: A double-blind randomized controlled trial in patients undergoing elective coronary artery bypass surgery. Clin Pharmacol Ther 2015; 99:381-9. [PMID: 25773594 DOI: 10.1002/cpt.106] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Accepted: 03/02/2015] [Indexed: 11/09/2022]
Abstract
Dipyridamole reduces reperfusion-injury in preclinical trials and may be beneficial in patients undergoing coronary angioplasty, but its effect on patients undergoing coronary artery bypass grafting (CABG) is unknown. We hypothesized that dipyridamole limits myocardial reperfusion-injury in patients undergoing CABG. The trial design was a double-blind trial randomizing between pretreatment with dipyridamole or placebo. In all, 94 patients undergoing elective on-pump CABG were recruited between February 2010 and June 2012. The primary endpoint was plasma high-sensitive (hs-) troponin-I at 6, 12, and 24 hours after reperfusion. Secondary endpoints were the occurrence of bleeding, arrhythmias, need for inotropic support, and intensive care unit length of stay. Finally, 79 patients (33 dipyridamole) were included in the per-protocol analysis. Dipyridamole did not significantly affect postoperative hs-troponin-I (change in plasma hs-troponin I -3% [95% confidence interval -23% to 36%]; P > 0.1). Secondary endpoints did not differ between groups. Dipyridamole prior to CABG does not significantly reduce postoperative hs-troponin release.
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Affiliation(s)
- S El Messaoudi
- Department of Pharmacology and Toxicology, Radboud University Medical Center, Nijmegen, the Netherlands.,Department of Cardiology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - C W Wouters
- Department of Pharmacology and Toxicology, Radboud University Medical Center, Nijmegen, the Netherlands.,Department of Cardiology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - H A van Swieten
- Department of Cardio-thoracic Surgery, Radboud University Medical Center, Nijmegen, the Netherlands
| | - P Pickkers
- Department of Intensive Care Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - L Noyez
- Department of Cardio-thoracic Surgery, Radboud University Medical Center, Nijmegen, the Netherlands
| | - P C Kievit
- Department of Cardiology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - E J Abbink
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - A Rasing-Hoogveld
- Department of Pharmacology and Toxicology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - T P Bouw
- Department of Intensive Care Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - J G Peters
- Department of Pharmacology and Toxicology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - M J H Coenen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - A R T Donders
- Department for Health Evidence, Radboud University Medical Center, Nijmegen, the Netherlands
| | - N P Riksen
- Department of Pharmacology and Toxicology, Radboud University Medical Center, Nijmegen, the Netherlands.,Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - G A Rongen
- Department of Pharmacology and Toxicology, Radboud University Medical Center, Nijmegen, the Netherlands.,Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
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Wijeysundera HC, Parmar G, Rongen GA, Floras JS. Reflex systemic sympatho-neural response to brachial adenosine infusion in treated heart failure. Eur J Heart Fail 2014; 13:475-81. [DOI: 10.1093/eurjhf/hfr005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Affiliation(s)
- Harindra C. Wijeysundera
- Mount Sinai Hospital and University Health Network Division of Cardiology, Faculty of Medicine; University of Toronto; Toronto ON Canada
- Sunnybrook Health Sciences Centre Division of Cardiology, Faculty of Medicine; University of Toronto; Suite A209D, 2075 Bayview Avenue Toronto ON Canada M4N 3M5
| | - Gurpreet Parmar
- Mount Sinai Hospital and University Health Network Division of Cardiology, Faculty of Medicine; University of Toronto; Toronto ON Canada
| | - Gerard A. Rongen
- Department of Pharmacology-Toxicology and General Internal Medicine; Nijmegen Netherlands
| | - John S. Floras
- Mount Sinai Hospital and University Health Network Division of Cardiology, Faculty of Medicine; University of Toronto; Toronto ON Canada
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Berry C, Layland J, Sood A, Curzen NP, Balachandran KP, Das R, Junejo S, Henderson RA, Briggs AH, Ford I, Oldroyd KG. Fractional flow reserve versus angiography in guiding management to optimize outcomes in non-ST-elevation myocardial infarction (FAMOUS-NSTEMI): rationale and design of a randomized controlled clinical trial. Am Heart J 2013; 166:662-668.e3. [PMID: 24093845 PMCID: PMC3807653 DOI: 10.1016/j.ahj.2013.07.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 07/01/2013] [Indexed: 01/21/2023]
Abstract
BACKGROUND In patients with acute non-ST-elevation myocardial infarction (NSTEMI), coronary arteriography is usually recommended; but visual interpretation of the angiogram is subjective. We hypothesized that functional assessment of coronary stenosis severity with a pressure-sensitive guide wire (fractional flow reserve [FFR]) would have additive diagnostic, clinical, and health economic utility as compared with angiography-guided standard care. METHODS AND DESIGN A prospective multicenter parallel-group 1:1 randomized controlled superiority trial in 350 NSTEMI patients with ≥1 coronary stenosis ≥30% severity (threshold for FFR measurement) will be conducted. Patients will be randomized immediately after coronary angiography to the FFR-guided group or angiography-guided group. All patients will then undergo FFR measurement in all vessels with a coronary stenosis ≥30% severity including culprit and nonculprit lesions. Fractional flow reserve will be disclosed to guide treatment in the FFR-guided group but not disclosed in the "angiography-guided" group. In the FFR-guided group, an FFR ≤0.80 will be an indication for revascularization by percutaneous coronary intervention or coronary artery bypass surgery, as appropriate. The primary outcome is the between-group difference in the proportion of patients allocated to medical management only compared with revascularization. Secondary outcomes include the occurrence of cardiac death or hospitalization for myocardial infarction or heart failure, quality of life, and health care costs. The minimum and average follow-up periods for the primary analysis are 6 and 18 months, respectively. CONCLUSIONS Our developmental clinical trial will address the feasibility of FFR measurement in NSTEMI and the influence of FFR disclosure on treatment decisions and health and economic outcomes.
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Affiliation(s)
- Colin Berry
- West of Scotland Heart and Lung Centre, Golden Jubilee National Hospital, Glasgow, United Kingdom; BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom.
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Notarius CF, Floras JS. Caffeine Enhances Heart Rate Variability in Middle-Aged Healthy, But Not Heart Failure Subjects. JOURNAL OF CAFFEINE RESEARCH 2012; 2:77-82. [PMID: 24761268 DOI: 10.1089/jcr.2012.0010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND In chronic heart failure (CHF) due to left ventricular dysfunction, diminished heart rate variability (HRV) is an independent predictor of poor prognosis. Caffeine has been shown to increase HRV in young healthy subjects. Such an increase may be of potential benefit to patients with CHF. OBJECTIVE We hypothesized that intravenous infusion of caffeine would increase HRV in CHF, and in age-matched healthy control subjects. METHODS On two separate days, 11 patients (1F) with CHF (age=51.3±4.6 years; left ventricular ejection fraction=18.6±2.7%; mean±standard error) and 10 healthy control subjects (age=48.0±4.0) according to a double-blind randomization design, received either saline or caffeine (4 mg/kg) infusion. We assessed HRV over 7 minutes of supine rest (fast Fourier Transform analysis) to determine total spectral power as well as its high-frequency (HF) (0.15-0.50 Hz) and low-frequency (LF) (0.05-0.15 Hz) components, and recorded muscle sympathetic nerve activity (MSNA) directly from the peroneal nerve (microneurography). RESULTS In healthy control subjects, compared with saline, caffeine reduced both heart rate and sympathetic nerve traffic (p≤0.003) and increased the ratio of HF/total power (p≤0.05). Baseline LF power and the ratio LF/HF were significantly lower in CHF compared with controls (p=0.02), but caffeine had no effect on any element of HRV. CONCLUSIONS Caffeine increases cardiac vagal heart rate modulation and reduces MSNA in middle-aged healthy subjects, but not in those with CHF.
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Affiliation(s)
- Catherine F Notarius
- Division of Cardiology, University Health Network and Mount Sinai Hospital, University of Toronto , Toronto, ON, Canada
| | - John S Floras
- Division of Cardiology, University Health Network and Mount Sinai Hospital, University of Toronto , Toronto, ON, Canada
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Ramakers BP, Riksen NP, van den Broek P, Franke B, Peters WHM, van der Hoeven JG, Smits P, Pickkers P. Circulating adenosine increases during human experimental endotoxemia but blockade of its receptor does not influence the immune response and subsequent organ injury. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2011; 15:R3. [PMID: 21211004 PMCID: PMC3222030 DOI: 10.1186/cc9400] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2010] [Revised: 10/01/2010] [Accepted: 01/06/2011] [Indexed: 02/01/2023]
Abstract
Introduction Preclinical studies have shown that the endogenous nucleoside adenosine prevents excessive tissue injury during systemic inflammation. We aimed to study whether endogenous adenosine also limits tissue injury in a human in vivo model of systemic inflammation. In addition, we studied whether subjects with the common 34C > T nonsense variant (rs17602729) of adenosine monophosphate deaminase (AMPD1), which predicts increased adenosine formation, have less inflammation-induced injury. Methods In a randomized double-blinded design, healthy male volunteers received 2 ng/kg E. Coli LPS intravenously with (n = 10) or without (n = 10) pretreatment with the adenosine receptor antagonist caffeine (4 mg/kg body weight). In addition, lipopolysaccharide (LPS) was administered to 10 subjects heterozygous for the AMPD1 34C > T variant. Results The increase in adenosine levels tended to be more pronounced in the subjects heterozygous for the AMPD1 34C > T variant (71 ± 22%, P=0.04), compared to placebo- (59 ± 29%, P=0.012) and caffeine-treated (53 ± 47%, P=0.29) subjects, but this difference between groups did not reach statistical significance. Also the LPS-induced increase in circulating cytokines was similar in the LPS-placebo, LPS-caffeine and LPS-AMPD1-groups. Endotoxemia resulted in an increase in circulating plasma markers of endothelial activation [intercellular adhesion molecule (ICAM) and vascular cell adhesion molecule (VCAM)], and in subclinical renal injury, measured by increased urinary excretion of tubular injury markers. The LPS-induced increase of these markers did not differ between the three groups. Conclusions Human experimental endotoxemia induces an increase in circulating cytokine levels and subclinical endothelial and renal injury. Although the plasma adenosine concentration is elevated during systemic inflammation, co-administration of caffeine or the presence of the 34C > T variant of AMPD1 does not affect the observed subclinical organ damage, suggesting that adenosine does not affect the inflammatory response and subclinical endothelial and renal injury during human experimental endotoxemia. Trial Registration ClinicalTrials (NCT): NCT00513110.
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Affiliation(s)
- Bart P Ramakers
- Department of Intensive Care Medicine, Radboud University Nijmegen Medical Center, Geert Grooteplein 10, 6500 HB Nijmegen, The Netherlands.
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Abstract
In the concentration range that is normally achieved in humans, e.g., after the drinking of coffee or in patients treated with theophylline, the cardiovascular effects of methylxanthines are primarily due to antagonism of adenosine A(1) and A(2) receptors. Inhibition of phosphodiesterases or mobilization of intracellular calcium requires much higher concentrations. In conscious humans, acute exposure to caffeine results in an increase in blood pressure by an increased total peripheral resistance, and a slight decrease in heart rate. This overall hemodynamic response is composed of direct effects of caffeine on vascular tone, on myocardial contractility and conduction, and on the sympathetic nervous system. Caffeine is the most widely consumed methylxanthine, mainly derived from coffee intake. Regular coffee consumption can affect various traditional cardiovascular risk factors, including a slight increase in blood pressure, an increase in plasma cholesterol and homocysteine levels, and a reduced incidence of type 2 diabetes mellitus. Although most prospective studies have not reported an association between coffee consumption and coronary heart disease, these findings do not exclude that the acute hemodynamic and neurohumoral effects of coffee consumption could have an adverse effect in selected patient groups who are more vulnerable for these effects, based on their genetic profile or medication use.
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Affiliation(s)
- Niels P Riksen
- Department of Pharmacology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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Abstract
Caffeine is the most widely consumed stimulating substance in the world. It is found in coffee, tea, soft drinks, chocolate, and many medications. Caffeine is a xanthine with various effects and mechanisms of action in vascular tissue. In endothelial cells, it increases intracellular calcium stimulating the production of nitric oxide through the expression of the endothelial nitric oxide synthase enzyme. Nitric oxide is diffused to the vascular smooth muscle cell to produce vasodilation. In vascular smooth muscle cells its effect is predominantly a competitive inhibition of phosphodiesterase, producing an accumulation of cAMP and vasodilation. In addition, it blocks the adenosine receptors present in the vascular tissue to produce vasoconstriction. In this paper the main mechanisms of action of caffeine on the vascular tissue are described, in which it is shown that caffeine has some cardiovascular properties and effects which could be considered beneficial.
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Riksen NP, Rongen GA, Smits P. Acute and long-term cardiovascular effects of coffee: Implications for coronary heart disease. Pharmacol Ther 2009; 121:185-91. [DOI: 10.1016/j.pharmthera.2008.10.006] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Accepted: 10/21/2008] [Indexed: 10/21/2022]
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Human in vivo research on the vascular effects of adenosine. Eur J Pharmacol 2008; 585:220-7. [DOI: 10.1016/j.ejphar.2008.01.053] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 12/21/2007] [Accepted: 01/22/2008] [Indexed: 11/19/2022]
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Notarius CF, Morris B, Floras JS. Caffeine Prolongs Exercise Duration in Heart Failure. J Card Fail 2006; 12:220-6. [PMID: 16624688 DOI: 10.1016/j.cardfail.2005.12.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2005] [Revised: 12/12/2005] [Accepted: 12/22/2005] [Indexed: 11/19/2022]
Abstract
BACKGROUND Caffeine increases submaximal exercise performance in healthy young subjects; its effects on exercise tolerance in heart failure (HF) have not been characterized. METHODS AND RESULTS To determine whether caffeine increases exercise tolerance in HF, caffeine (4 mg/kg intravenously, equivalent to 2 cups of coffee) or vehicle were infused into 10 treated HF patients (left ventricular ejection fraction 25 +/- 2 %), and 10 age-matched normal subjects (N) on 2 separate days in a double-blind, randomized, crossover design. We measured heart rate, blood pressure, and ventilation at rest and during graded cycling (15 W/minute) to peak effort. Peak oxygen consumption was unaffected in either group. Mean exercise time was unchanged in N (1,013 +/- 87 versus 988 +/- 107 seconds; P = .86) but was significantly increased by caffeine in HF (from 511 +/- 28 to 560 +/- 37 seconds; P = .004) despite an increase in peak minute ventilation (P < .05). Resting and peak blood pressures were higher after caffeine (P < .05) in HF, not N. CONCLUSION Caffeine allows HF patients to exercise longer at peak effort.
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Affiliation(s)
- Catherine F Notarius
- Division of Cardiology and Faculty of Medicine, University Health Network and Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
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Riksen NP, van Ginneken EEM, van den Broek PHH, Smits P, Rongen GA. In vivo evidence against a role for adenosine in the exercise pressor reflex in humans. J Appl Physiol (1985) 2005; 99:522-7. [PMID: 15817726 DOI: 10.1152/japplphysiol.00108.2005] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The pressor response to exercise is of great importance in both physiology and pathophysiology. Whether endogenous adenosine is a trigger for this reflex remains controversial. Muscle interstitial adenosine concentration can be determined by microdialysis. However, there are indications that local muscle cell damage by the microdialysis probe confounds these measurements in exercising muscle. Therefore, we used the nucleoside uptake inhibitor dipyridamole as pharmacological tool to bypass this confounding. We used microdialysis probes to measure endogenous adenosine in forearm skeletal muscle of healthy volunteers during two cycles of 15 min of intermittent isometric handgripping. During the second contraction, dipyridamole (12 microg.min(-1).dl forearm(-1)) was administered into the brachial artery. Dipyridamole potentiated the exercise-induced increase in dialysate adenosine from 0.30 +/- 0.08 to 0.48 +/- 0.10 micromol/l (n = 9, P < 0.05), but it did not potentiate the exercise-induced increase in blood pressure. A time-control study without dipyridamole revealed no difference in exercise-induced increase in adenosine between both contractions (n = 8). To exclude the possibility that the dipyridamole-induced increase in dialysate adenosine originates from extravasation of increased circulating adenosine, we simultaneously measured adenosine with microdialysis probes in forearm muscle and antecubital vein. In a separate group of nine volunteers, simultaneous intrabrachial infusion of 100 microg.min(-1).dl(-1) dipyridamole and 5 microg.min(-1).dl(-1) adenosine increased dialysate adenosine from the intravenous but not the interstitial probe, indicating preserved endothelial barrier function for adenosine. We conclude that dipyridamole significantly inhibits uptake of interstitial adenosine without affecting the pressor response to exercise, suggesting that interstitial adenosine is not involved in the pressor response to rhythmic isometric exercise.
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Affiliation(s)
- Niels P Riksen
- Dept. of Pharmacology-Toxicology 233, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands.
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Hirata K, Shimada K, Watanabe H, Otsuka R, Tokai K, Yoshiyama M, Homma S, Yoshikawa J. Black tea increases coronary flow velocity reserve in healthy male subjects. Am J Cardiol 2004; 93:1384-8, A6. [PMID: 15165919 DOI: 10.1016/j.amjcard.2004.02.035] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2003] [Revised: 02/18/2004] [Accepted: 02/18/2004] [Indexed: 11/24/2022]
Abstract
Epidemiologic studies suggest that tea consumption decreases the risk for cardiovascular events. However, there has been no clinical report examining the effects of tea consumption on coronary circulation. The purpose of this study was to evaluate the effects of black tea on coronary flow velocity reserve (CFVR) using transthoracic Doppler echocardiography (TTDE). This was a double-blind crossover study of 10 healthy male volunteers conducted to compare the effects of black tea and caffeine on coronary circulation. The coronary flow velocity of the left anterior descending coronary artery was measured at baseline and at hyperemia during adenosine triphosphate infusion by TTDE to determine CFVR. The CFVR ratio was defined as the ratio of CFVR after beverage consumption to CFVR before beverage consumption. All data were divided into 2 groups according to beverage type: group T (black tea) and group C (caffeine). Two-way analysis of variance showed a significant group effect and interaction in CFVR before and after beverage consumption (p = 0.001). CFVR significantly increased after tea consumption in group T (4.5 +/- 0.9 vs 5.2 +/- 0.9, p <0.0001). The CFVR ratio of group T was larger than that of group C (1.18 +/- 0.07 vs 1.04 +/- 0.08, p = 0.002). Acute black tea consumption improves coronary vessel function, as determined by CFVR.
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Affiliation(s)
- Kumiko Hirata
- Department of Medicine, Division of Cardiology, College of Physicians & Surgeons, Columbia University, New York, NY, USA
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Notarius CF, Atchison DJ, Rongen GA, Floras JS. Effect of adenosine receptor blockade with caffeine on sympathetic response to handgrip exercise in heart failure. Am J Physiol Heart Circ Physiol 2001; 281:H1312-8. [PMID: 11514302 DOI: 10.1152/ajpheart.2001.281.3.h1312] [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
Adenosine (Ado) increases muscle sympathetic nerve activity (MSNA) reflexively. Plasma Ado and MSNA are elevated in heart failure (HF). We tested the hypothesis that Ado receptor blockade by caffeine would attenuate reflex MSNA responses to handgrip (HG) and posthandgrip ischemia (PHGI) and that this action would be more prominent in HF subjects than in normal subjects. We studied 12 HF subjects and 10 age-matched normal subjects after either saline or caffeine (4 mg/kg) infusion during isometric [30% of maximal voluntary contraction (MVC)] and isotonic (10%, 30%, and 50%) HG exercise, followed by 2 min of PHGI. In normal subjects, caffeine did not block increases in MSNA during PHGI after 50% HG. In HF subjects, caffeine abolished MSNA responses to PHGI after both isometric and 50% isotonic exercise (P < 0.05) but MSNA responses during HG were unaffected. These findings are consistent with muscle metaboreflex stimulation by endogenous Ado during ischemic or intense nonischemic HG in HF and suggest an important sympathoexcitatory role for endogenous Ado during exercise in this condition.
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Affiliation(s)
- C F Notarius
- Division of Cardiology, Toronto General and Mount Sinai Hospitals, University of Toronto, Toronto, Ontario, Canada
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