(Circulation. 1996;94:130-134.)
© 1996 American Heart Association, Inc.
Articles |
the Research Institute of Angiocardiology and Cardiovascular Clinic, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Correspondence to Kensuke Egashira, MD, PhD, Research Institute of Angiocardiology and Cardiovascular Clinic, Kyushu University School of Medicine, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-82, Japan.
| Abstract |
|---|
|
|
|---|
Methods and Results The effect of intracoronary infusion of L-arginine (50 mg/min) on acetylcholine-induced coronary vasomotion was studied in eight patients with microvascular angina and eight control subjects. The responses of the large epicardial coronary artery diameter and coronary blood flow were measured with coronary arteriography and an intracoronary Doppler catheter, respectively. Acetylcholine increased coronary blood flow with modest vasoconstriction of the large coronary artery without altering arterial pressure and heart rate. The acetylcholine-induced increases in coronary blood flow were significantly less (P<.01) in patients than in control subjects. L-Arginine significantly augmented the coronary blood flow responses to acetylcholine in patients, but not in control subjects. L-Arginine did not alter responses of the large coronary artery in either group.
Conclusions Study results suggest that L-arginine improved endothelium-dependent vasodilation of coronary microcirculation in patients with microvascular angina pectoris.
Key Words: endothelium-derived factors coronary disease syndrome X angina
| Introduction |
|---|
|
|
|---|
L-Arginine is a precursor of endothelium-derived nitric oxide.5 Thus, supplementation with L-arginine may facilitate production of nitric oxide and augment endothelium-dependent vasodilation. In fact, it has been shown that supplementation with L-arginine improves attenuated endothelium-dependent coronary vasodilation in animals and humans with hypercholesterolemia.6 7 8 9 However, we recently demonstrated that intracoronary infusion of L-arginine did not alter attenuated acetylcholine-induced endothelium-dependent coronary vasodilation in patients with coronary artery disease and hypertension.10 Therefore, it appears that the mechanisms of endothelial dysfunction may differ depending on the cause and severity of vascular disease.11 12 It is not known whether L-arginine improves endothelial dysfunction in patients with microvascular angina.
In the present study, we examined the effects of intracoronary infusion of L-arginine on endothelium-dependent coronary vasodilation evoked with acetylcholine in patients with microvascular angina.
| Methods |
|---|
|
|
|---|
|
|
Study Protocol
The study protocols were approved by the Institutional Review Committee on Human Research of the Research Institute of Angiocardiology, Kyushu University School of Medicine. Written informed consent was obtained from each patient.
Cardiac catheterization was performed with the participant in the fasting state after premedication with 5 mg diazepam PO. Antianginal medications were discontinued for
24 hours before the study (Table 1
).
Thirty minutes after the diagnostic coronary arteriography was completed, the following studies were performed while the diameter of the large epicardial coronary arteries and coronary blood flow (CBF) were measured: (1) acetylcholine at the graded doses (1, 3, 10, and 30 µg/min; 2 minutes each) was infused into the Doppler catheter, and coronary arteriography was performed after each dose of acetylcholine; (2) 10 minutes later, L-arginine (50 mg/min for 10 minutes) was infused into the left coronary artery through the guiding catheter, and coronary arteriography was performed; (3) the acetylcholine study was repeated while L-arginine was simultaneously infused; (4) 10 minutes after the infusion of L-arginine was stopped, isosorbide dinitrate (2 mg) was administered through the guiding catheter, and coronary arteriography was performed 2 minutes later; and (5) papaverine (10 mg) was injected through the guiding catheter, and coronary arteriography was performed 2 minutes later.
In all eight patients and in five control subjects, a catheter was inserted into the coronary sinus vein. Paired samples of arterial and coronary venous blood were taken before and 2 minutes after papaverine administration for measurement of plasma lactate. The plasma lactate concentration was measured immediately after sampling with a calibrated lactate analyzer (OMRON Inc).
Arterial pressure, heart rate, and ECGs were continuously monitored and recorded with the use of a polygraph system (Nihon-Kohden).
Quantitative Coronary Arteriography
The diameter at the proximal segment of the left anterior descending coronary artery distal to the Doppler catheter was determined with the use of a videodensitometric analysis system as we described previously.1 10 13 14 15 After selection of the view that allowed the best visualization of the left anterior descending coronary artery, coronary angiograms were recorded with a Siemens angiographic system.
The diameter measurements were done three times in a blinded manner without knowledge of the clinical characteristics of the patients, and the averaged value was used for analysis. Two or more branch points were determined to allow assessment of serial changes in the diameter of the same arterial site in response to drugs. The size of a Judkins catheter was used to calibrate the arterial diameter.
Measurements of CBF and Velocity
An 8F angioplasty guiding catheter was introduced into the left main coronary artery via the femoral approach. A 3F Doppler flow velocity catheter (model DC-201, Millar Instruments) was introduced into the proximal left anterior descending coronary artery. Blood flow velocity signals were obtained with a Millar DC-101 Velocimeter. The increases in CBF in response to acetylcholine and nitrate were estimated on the basis of the product of the mean CBF velocity and the cross-sectional area of the proximal left anterior descending coronary artery segment distal to the tip of the Doppler catheter.1 10 13 14 15 The increase in CBF in response to papaverine was assessed from the product of mean blood flow velocity and the baseline cross-sectional area. Changes in estimated CBF in response to drugs were expressed as percent changes from the baseline value.
Statistical Analysis
Data are given as mean±SD. The effects of L-arginine on acetylcholine-induced changes in hemodynamic parameters were compared with the use of two-way ANOVA with repeated measures followed by Bonferroni's multiple-comparison tests. Clinical characteristics such as age and cholesterol levels were compared with the use of a Student's t test.
The effects of clinical characteristics on the CBF response to acetylcholine were examined. Simple linear regression analysis was used to examine the effects of continuous variables (eg, age, cholesterol levels). The Student's t test was used to examine the effects of sex, smoking habit, and hypertension. Finally, the effects of these factors were examined through multiple linear regression analysis. A probability level of <.05 was considered statistically significant.
| Results |
|---|
|
|
|---|
The lactate extraction ratio [(arterial lactate concentration minus venous lactate concentration)/arterial lactate concentrationx100 (%)] before and after intracoronary papaverine administration is presented in Table 2
. Papaverine caused myocardial lactate production in all of the patients but not in the control subjects tested. Five of the eight patients developed chest pain, and five patients developed ischemic ST-segment changes, whereas none of the control subjects had myocardial lactate production, chest pain, or ischemic ST-segment changes.
Effects of L-Arginine on Acetylcholine-Induced Changes in Coronary Artery Diameter and CBF
Table 3
shows changes in the diameter of large epicardial coronary arteries in response to intracoronary infusion of acetylcholine before and during simultaneous infusion of L-arginine at 50 mg/min. The baseline arterial diameter (2.6±0.2 and 3.0±0.1 mm, P=NS), mean arterial pressure (84±6 and 86±4 mm Hg, P=NS), and heart rate (66±4 and 63±4 bpm, P=NS) did not differ between control subjects and patients. Before L-arginine, the diameter of the large epicardial coronary arteries decreased slightly but significantly (P<.05) in response to the high dose (30 µg/min) of acetylcholine in control subjects and patients. The responses of the large epicardial coronary arteries to acetylcholine were similar between the two groups. The infusion of L-arginine did not alter the baseline diameter of the large epicardial coronary artery, mean arterial pressure, or heart rate. L-Arginine had no effect on responses to acetylcholine in either group.
|
Acetylcholine significantly (P<.01) increased CBF in a dose-dependent manner in control subjects but not in the patients (Figure
). Before L-arginine infusion, the percent increases in CBF evoked with acetylcholine were significantly less (P<.01) in the patients than in control subjects. The percent increase in CBF evoked with papaverine was 332±43% in control subjects and 298±48% in patients (NS). The percent increase in CBF evoked with isosorbide dinitrate was 116±22% in control subjects and 130±34% in patients (NS).
|
Intracoronary infusion of L-arginine did not alter the CBF responses to acetylcholine in control subjects (Figure
). In contrast, in patients with angina and normal coronary arteriograms, L-arginine infusion significantly (P<.01 by two-way ANOVA) augmented the CBF responses to acetylcholine (Figure
). However, the increases in CBF responses to acetylcholine during L-arginine infusion were less (P<.05 by two-way ANOVA) in the patients than in the control subjects.
In either the patients or control subjects, the maximal increase in CBF evoked with acetylcholine did not significantly correlate with age, cholesterol level, or other clinical characteristics. Multiple linear regression analysis revealed that the presence of microvascular angina was an independent factor (P<.01) for predicting impaired CBF response to acetylcholine.
| Discussion |
|---|
|
|
|---|
Effects of L-Arginine on Coronary Microcirculation
It has been shown that acetylcholine-induced vasodilation of coronary microcirculation is impaired in various pathophysiological states,11 12 13 14 15 16 17 including microvascular angina.1 2 However, the effects of L-arginine on endothelium-dependent dilation of coronary arteries have not been investigated in patients with microvascular angina.
L-Arginine is the precursor of endothelium-derived nitric oxide.5 Thus, supplementation with L-arginine may facilitate production of nitric oxide and improve endothelium-dependent vasodilation. In fact, it has been shown that L-arginine improves defective endothelium-dependent vasodilation in patients with hypercholesterolemia6 9 and those who have undergone cardiac transplantation18 but not in patients with coronary artery disease and hypertension.10
This study demonstrated for the first time that intracoronary infusion of L-arginine improves acetylcholine-induced vasodilation of coronary microcirculation in patients with microvascular angina. Since acetylcholine-induced coronary vasodilation in patients is mediated by endothelium-derived nitric oxide,19 20 it is reasonable to assume that impaired acetylcholine-induced endothelium-dependent vasodilation of coronary microcirculation in patients with microvascular angina resulted from defective synthesis and/or release of nitric oxide. However, the mechanism by which L-arginine improved endothelium-dependent vasodilation of coronary microcirculation is not known. L-Arginine supplementation may have effects at several levels in the L-arginine/nitric oxide pathway.21 L-Arginine supplementation might have increased nitric oxide synthesis by increasing the availability of L-arginine for the reaction mediated by nitric oxide synthase, caused upregulation of nitric oxide synthase activity, and inhibited augmented inactivation of nitric oxide by superoxide anions. L-Arginine might have reduced the effects of augmented release of endothelium-derived vasoconstrictors. Further studies are needed to investigate the mechanisms by which L-arginine supplementation improves microvascular endothelial function in these patients.
The fact that reversal of acetylcholine-induced coronary vasodilation by L-arginine was incomplete in the patients may be related to the following possibilities. First, endothelium-derived hyperpolarizing factor might be involved.12 Second, the dose or duration of L-arginine supplementation may have been inadequate. Third, the incomplete reversal by L-arginine might be due to the presence of structural changes in coronary microcirculation (the reduced capillary density and microvascular luminal narrowing due to medial thickening and endothelial swelling) in patients.22
The effect of L-arginine on acetylcholine-induced vasodilation of coronary microcirculation might not be nonspecific, because it was reported that D-arginine did not affect acetylcholine-induced vasodilation of forearm blood vessels in humans.23
Effects of L-Arginine on Large Epicardial Coronary Artery
The degrees of the vasoconstriction in response to acetylcholine were similar between the patients and control subjects. Although normal humans should exhibit acetylcholine-induced vasodilation of large epicardial coronary artery,24 acetylcholine is reported to induce vasoconstriction of angiographically normal segments of coronary arteries in patients with risk factors for coronary artery disease.13 14 15 16 17 Our patients had risk factors such as age of >50 years, smoking, arterial hypertension, and mild hypercholesterolemia.
L-Arginine did not affect acetylcholine-induced vasomotion of large epicardial coronary artery in patients with microvascular angina or control subjects in the present study. The reason why L-arginine did not improve acetylcholine-induced vasomotion of large epicardial coronary arteries in these patients is not known, but it might be related to different stages of arteriosclerotic process in the large epicardial and resistance coronary arteries.
Study Limitations
Many of our patients and control subjects had coronary risk factors. However, it is unlikely that the presence of the risk factors influenced the present results, because the incidence of those factors did not differ between the two groups. The presence of microvascular angina was an independent factor predicting impaired CBF response to acetylcholine.
Conclusions
This study demonstrated that L-arginine improved endothelium-dependent dilation of coronary microcirculation in patients with microvascular angina, suggesting that endothelial dysfunction of coronary microcirculation in these patients may be related to the defective synthesis and/or release of nitric oxide. Further studies are needed to elucidate the cause-and-effect relationship between the defective release of nitric oxide and myocardial ischemia in patients with microvascular angina.
| Acknowledgments |
|---|
Received January 10, 1995; revision received November 21, 1995; accepted December 10, 1995.
| References |
|---|
|
|
|---|
2.
Quyyumi AA, Cannon RO III, Panza JA, Diodati JG, Epstein SE. Endothelial dysfunction in patients with chest pain and normal coronary arteries. Circulation. 1994;86:1864-1871.
3.
Cannon RO, Camici PG, Epstein SE. Pathophysiological dilemma of syndrome X. Circulation. 1993;85:883-892.
4. Maseri A, Crea F, Kaski JC, Crake T. Mechanism of angina pectoris in syndrome X. J Am Coll Cardiol. 1991;17:499-506.[Medline] [Order article via Infotrieve]
5. Palmer RMJ, Ashton DS, Moncada S. Vascular endothelial cells synthesize nitric oxide from L-arginine. Nature. 1988;333:664-666.[Medline] [Order article via Infotrieve]
6. Drexler H, Zeiher AM, Meinzer K, Just H. Correction of endothelial dysfunction in coronary microcirculation of hypercholesterolemic patients by L-arginine. Lancet. 1991;338:1546-1550.[Medline] [Order article via Infotrieve]
7.
Tanner FC, Noll G, Boulanger CM, Luscher TF. Oxidized low-density proteins inhibit relaxations of porcine coronary arteries: role of scavenger receptor and endothelium-derived nitric oxide. Circulation. 1991;83:2012-2020.
8.
Kuo L, Davis MJ, Cannon MS, Chilian WM. Pathophysiological consequences of atherosclerosis extend into the coronary microcirculation: restoration of endothelium-dependent responses by L-arginine. Circ Res. 1992;70:465-476.
9. Creager MA, Gallagher SJ, Girerd XJ, Coleman SM, Dzau VJ, Cooke JP. L-Arginine improves endothelium-dependent vasodilation in hypercholesterolemic humans. J Clin Invest. 1992;90:1248-1253.
10. Hirooka Y, Egashira K, Imaizumi T, Tagawa T, Kai H, Sugimachi M, Takeshita A. Effects of L-arginine on acetylcholine-induced endothelium-dependent vasodilation differ between the coronary and forearm vasculatures in humans. J Am Coll Cardiol. 1994;24:948-955.[Abstract]
11.
Flavahan NA. Atherosclerosis and lipoprotein-induced endothelial dysfunction: potential mechanisms underlying reduction in endothelium-derived relaxing factor/nitric oxide activity. Circulation. 1992;85:1927-1938.
12. Luscher TF, Richard V, Tschudi M, Yang Z, Boulanger C. Endothelial control of vascular tone in large and small coronary arteries. J Am Coll Cardiol. 1990;15:512-527.
13. Egashira K, Inou T, Hirooka Y, Yamada A, Maruoka Y, Kai H, Suzuki S, Takeshita A. Impaired coronary blood flow response to acetylcholine in patients with coronary risk factors and proximal atherosclerotic lesions. J Clin Invest. 1993;91:29-37.
14.
Egashira K, Inou T, Hirooka Y, Kai H, Sugimachi M, Suzuki S, Kuga T, Urabe Y, Takeshita A. Effects of age on endothelium-dependent vasodilation of resistance coronary artery by acetylcholine in humans. Circulation. 1993;88:77-81.
15.
Egashira K, Hirooka Y, Kai H, Sugimachi M, Suzuki S, Inou T, Takeshita A. Reduction in serum cholesterol with pravastatin improves endothelium-dependent coronary vasomotion in patients with hypercholesterolemia. Circulation. 1994;89:2519-2524.
16.
Vita JA, Treasure CB, Nabel EG, McLenachan JM, Fish RD, Yeung AC, Vekstein VI, Selwyn AP, Ganz P. Coronary vasomotor response to acetylcholine relates to risk factors for coronary artery disease. Circulation. 1990;81:491-497.
17. Zeiher AM, Drexler H, Saubier B, Just H. Endothelium-mediated coronary blood flow modulation in humans: effects of age, atherosclerosis, hypercholesterolemia, and hypertension. J Clin Invest. 1993;92:652-662.
18.
Drexler H, Fischell TA, Pinto FJ, Chenzbraun A, Botas J, Cooke JP, Alderman EL. Effect of L-arginine on coronary endothelial function in cardiac transplant patients: relation to vessel wall morphology. Circulation. 1994;89:1615-1623.
19.
Quyyumi AA, Dakak N, Andrews NP, Gilligan DM, Panza JA, Cannon RO. Contribution of nitric oxide to metabolic coronary vasodilation in the human heart. Circulation. 1995;91:320-326.
20. Quyyumi AA, Dakak N, Andrews NP, Husain S, Arora S, Gilligan DM, Panza JA, Cannon RO III. Nitric oxide activity in the human coronary circulation: impact of risk factors for coronary atherosclerosis. J Clin Invest. 1995;95:1747-1755.
21.
Moncada S, Higgs A. The L-arginine-nitric oxide pathway. N Engl J Med. 1993;329:2002-2012.
22.
Mosseri M, Schaper J, Admon D, Hasin Y, Gotsman MS, Sapoznikov D, Pickering JG, Yarom R. Coronary capillaries in patients with congestive cardiomyopathy or angina pectoris with patent main coronary arteries. Circulation. 1991;84:203-210.
23.
Imaizumi T, Hirooka Y, Masaki H, Harada S, Momohara M, Tagawa T, Takeshita A. Effects of L-arginine on forearm vessels and responses to acetylcholine. Hypertension. 1992;20:511-517.
24. Ludmer PL, Selwyn AP, Shock TL, Wayne RR, Mudge GH, Alexander RW, Ganz P. Paradoxical vasoconstriction induced by acetylcholine in atherosclerotic coronary arteries. N Engl J Med. 1986;315:1046-1051.[Abstract]
This article has been cited by other articles:
![]() |
D Tousoulis, C Xenakis, C Tentolouris, G Davies, C Antoniades, T Crake, and C Stefanadis Effects of vitamin C on intracoronary L-arginine dependent coronary vasodilatation in patients with stable angina Heart, October 1, 2005; 91(10): 1319 - 1323. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. L. Gornik and M. A. Creager Arginine and Endothelial and Vascular Health J. Nutr., October 1, 2004; 134(10): 2880S - 2887S. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. H. Yang, G. W. Barsness, B. J. Gersh, K. Chandrasekaran, and A. Lerman Current and Future Treatment Strategies for Refractory Angina Mayo Clin. Proc., October 1, 2004; 79(10): 1284 - 1292. [Abstract] [PDF] |
||||
![]() |
M. Kayikcioglu, S. Payzin, O. Yavuzgil, H. Kultursay, L. H. Can, and I. Soydan Benefits of statin treatment in cardiac syndrome-X Eur. Heart J., November 2, 2003; 24(22): 1999 - 2005. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Arroyo-Espliguero, N. Mollichelli, P. Avanzas, E. Zouridakis, V. R Newey, D. K Nassiri, and J. C. Kaski Chronic inflammation and increased arterial stiffness in patients with cardiac syndrome X Eur. Heart J., November 2, 2003; 24(22): 2006 - 2011. [Abstract] [Full Text] [PDF] |
||||
![]() |
D Tousoulis, G J Davies, C Tentolouris, T Crake, G Goumas, C Stefanadis, and P Toutouzas Effects of L-arginine on flow mediated dilatation induced by atrial pacing in diseased epicardial coronary arteries Heart, May 1, 2003; 89(5): 531 - 534. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Piatti, G. Fragasso, L. D. Monti, E. Setola, P. Lucotti, I. Fermo, R. Paroni, E. Galluccio, G. Pozza, S. Chierchia, et al. Acute Intravenous l-Arginine Infusion Decreases Endothelin-1 Levels and Improves Endothelial Function in Patients With Angina Pectoris and Normal Coronary Arteriograms: Correlation With Asymmetric Dimethylarginine Levels Circulation, January 28, 2003; 107(3): 429 - 436. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Tousoulis, C. Antoniades, C. Tentolouris, G. Goumas, C. Stefanadis, and P. Toutouzas L-Arginine in cardiovascular disease: dream or reality? Vascular Medicine, August 1, 2002; 7(3): 203 - 211. [Abstract] [PDF] |
||||
![]() |
J. L. Houghton, E. F. Philbin, D. S. Strogatz, M. T. Torosoff, S. A. Fein, P. A. Kuhner, V. E. Smith, and A. A. Carr The presence of African American race predicts improvement in coronary endothelial function after supplementary L-arginine J. Am. Coll. Cardiol., April 17, 2002; 39(8): 1314 - 1322. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Carrier, M. Pellerin, L. P. Perrault, D. Bouchard, P. Page, N. Searle, and J. Lavoie Cardioplegic arrest with L-arginine improves myocardial protection: results of a prospective randomized clinical trial Ann. Thorac. Surg., March 1, 2002; 73(3): 837 - 841. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. J. Maxwell, M. P. Zapien, G. L. Pearce, G. MacCallum, and P. H. Stone Randomized trial of a medical food for the dietary management of chronic, stable angina J. Am. Coll. Cardiol., January 2, 2002; 39(1): 37 - 45. [Abstract] [Full Text] [PDF] |
||||
![]() |
D Tousoulis, G J Davies, C Tentolouris, G Goumas, C Stefanadis, and P Toutouzas Vasomotor effects of L- and D-arginine in stenotic atheromatous coronary plaque Heart, September 1, 2001; 86(3): 296 - 301. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. lannuzzi, G. Jannuzzo, C. Sapio, P. Pauciullo, D. Jorio, N. Spampinato, M. Mancini, and P. Rubba L-Arginine Improves Post-Ischemic Vasodilation in Coronary Heart Disease Patients Taking Vasodilating Drugs Journal of Cardiovascular Pharmacology and Therapeutics, June 1, 2001; 6(2): 121 - 127. [Abstract] [PDF] |
||||
![]() |
A. Blum, L. Hathaway, R. Mincemoyer, W. H. Schenke, M. Kirby, G. Csako, M. A. Waclawiw, J. A. Panza, and R. O. Cannon III Oral L-Arginine in Patients With Coronary Artery Disease on Medical Management Circulation, May 9, 2000; 101(18): 2160 - 2164. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. W. Wallace and W. L. Tom Interaction of L-Arginine and Phosphodiesterase Inhibitors in Vasodilation of the Porcine Internal Mammary Artery Anesth. Analg., April 1, 2000; 90(4): 840 - 846. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Ono, H. Ono, H. Matsuoka, T. Fujimori, and E. D. Frohlich Apoptosis, Coronary Arterial Remodeling, and Myocardial Infarction After Nitric Oxide Inhibition in SHR Hypertension, October 1, 1999; 34(4): 609 - 616. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. E. Reis, R. Holubkov, J. S. Lee, B. Sharaf, N. Reichek, W. J. Rogers, E. G. Walsh, A. R. Fuisz, R. Kerensky, K. M. Detre, et al. Coronary flow velocity response to adenosine characterizes coronary microvascular function in women with chest pain and no obstructive coronary disease: Results from the pilot phase of the Women's Ischemia Syndrome Evaluation (WISE) Study J. Am. Coll. Cardiol., May 1, 1999; 33(6): 1469 - 1475. [Abstract] [Full Text] [PDF] |
||||
![]() |
D Tousoulis, C Tentolouris, T Crake, G Katsimaglis, C Stefanadis, P Toutouzas, and G J Davies Effects of L- and D-arginine on the basal tone of human diseased coronary arteries and their responses to substance P Heart, May 1, 1999; 81(5): 505 - 511. [Abstract] [Full Text] |
||||
![]() |
M. Bottcher, H. E. Botker, H. Sonne, T. T. Nielsen, and J. Czernin Endothelium-Dependent and -Independent Perfusion Reserve and the Effect of L-arginine on Myocardial Perfusion in Patients With Syndrome X Circulation, April 13, 1999; 99(14): 1795 - 1801. [Abstract] [Full Text] [PDF] |
||||
![]() |
K.-i. Kikuta, T. Sawamura, S. Miwa, N. Hashimoto, and T. Masaki High-Affinity Arginine Transport of Bovine Aortic Endothelial Cells Is Impaired by Lysophosphatidylcholine Circ. Res., November 30, 1998; 83(11): 1088 - 1096. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. F Bellamy, J. Goodfellow, A. C Tweddel, F. D.J Dunstan, M. J Lewis, and A. H Henderson Syndrome X and endothelial dysfunction Cardiovasc Res, November 1, 1998; 40(2): 410 - 417. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Dakak, S. Husain, D. Mulcahy, N. P. Andrews, J. A. Panza, M. Waclawiw, W. Schenke, and A. A. Quyyumi Contribution of Nitric Oxide to Reactive Hyperemia : Impact of Endothelial Dysfunction Hypertension, July 1, 1998; 32(1): 9 - 15. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. M. F. Wever, T. F. Luscher, F. Cosentino, and T. J. Rabelink Atherosclerosis and the Two Faces of Endothelial Nitric Oxide Synthase Circulation, January 13, 1998; 97(1): 108 - 112. [Full Text] [PDF] |
||||
![]() |
U. Solzbach, B. Hornig, M. Jeserich, and H. Just Vitamin C Improves Endothelial Dysfunction of Epicardial Coronary Arteries in Hypertensive Patients Circulation, September 2, 1997; 96(5): 1513 - 1519. [Abstract] [Full Text] |
||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Circulation Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 1996 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |