This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Collins, P. Articles by Fox, K. Search for Related Content PubMed PubMed Citation Articles by Collins, P. Articles by Fox, K. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Hazardous Substances DB POTASSIUM CHLORIDE

Circulation, Vol 87, 80-85, Copyright © 1993 by American Heart Association

ARTICLES

Hemoglobin inhibits endothelium-dependent relaxation to acetylcholine in human coronary arteries in vivo

P Collins, J Burman, HI Chung and K Fox
Department of Cardiac Medicine, National Heart and Lung Institute, London, UK.

BACKGROUND. The endothelium can regulate vascular tone by releasing both endothelium-derived relaxing factor (EDRF or nitric oxide) and contracting factors. To date, there has only been circumstantial evidence to indicate EDRF activity in vivo in human coronary arteries. Using human hemoglobin as a specific inhibitor, the hypothesis that acetylcholine-induced coronary vasodilation is due to EDRF release was tested. METHODS AND RESULTS. We studied the response of normal coronary arteries to acetylcholine (an endothelium-dependent vasodilator) and isosorbide dinitrate (an endothelium-independent vasodilator) in seven patients. The specificity of any vasodilator response was assessed by the infusion of reduced free human hemoglobin. Hemoglobin 10(-5) M infusion alone had no effect on coronary artery diameter. Drugs were infused into the coronary artery, and the diameter changes were assessed by quantitative angiography. Acetylcholine 10(-7) M increased left anterior descending coronary artery diameter from control: 2.30 +/- 0.12 mm to 2.79 +/- 0.20 mm (mean +/- SEM, n = 7, p < 0.01). Hemoglobin both in a concentration of 10(-6) M and 10(-5) M reversed this vasodilator effect, causing constriction to 2.11 +/- 0.18 mm (p < 0.001 compared with acetylcholine 10(-7) M) and 2.29 +/- 0.14 mm (p < 0.05 compared with acetylcholine 10(-7) M). Isosorbide dinitrate in the presence of hemoglobin caused dilatation of the coronary artery in all cases to 3.04 +/- 0.24 mm (p < 0.001 compared with acetylcholine 10(-7) M and hemoglobin 10(-6) M). CONCLUSIONS. Using a specific inhibitor of nitric oxide, reduced free hemoglobin, we have demonstrated that basal EDRF release does not appear to play an important role in the maintenance of human epicardial coronary artery diameter in vivo but is responsible for the acetylcholine-induced dilatation.

This article has been cited by other articles:

				K. L. Chaichana, A. P. Levy, R. Miller-Lotan, S. Shakur, and R. J. Tamargo Haptoglobin 2-2 Genotype Determines Chronic Vasospasm After Experimental Subarachnoid Hemorrhage Stroke, December 1, 2007; 38(12): 3266 - 3271. [Abstract] [Full Text] [PDF]

				M. R. Forrest, A. H. Chester, and D. Royston The Effects of Diaspirin Cross-Linked Hemoglobin on the Tone of Human Saphenous Vein Anesth. Analg., February 1, 2001; 92(2): 324 - 328. [Abstract] [Full Text] [PDF]

				S W Turner, S Hunter, and J P Wyllie The natural history of ventricular septal defects Arch. Dis. Child., November 1, 1999; 81(5): 413 - 416. [Abstract] [Full Text] [PDF]

				C. S Hayward, R. P Kelly, and P. S Macdonald Inhaled nitric oxide in cardiology practice Cardiovasc Res, August 15, 1999; 43(3): 628 - 638. [Abstract] [Full Text] [PDF]

				A. Caron, P. Menu, B. Faivre-Fiorina, P. Labrude, A. I. Alayash, and C. Vigneron Cardiovascular and hemorheological effects of three modified human hemoglobin solutions in hemodiluted rabbits J Appl Physiol, February 1, 1999; 86(2): 541 - 548. [Abstract] [Full Text] [PDF]

				M. Flesch, A. Schwarz, and M. Bohm Effects of red and white wine on endothelium-dependent vasorelaxation of rat aorta and human coronary arteries Am J Physiol Heart Circ Physiol, October 1, 1998; 275(4): H1183 - H1190. [Abstract] [Full Text] [PDF]

				Y. Asano, R. C. Koehler, J. A. Ulatowski, R. J. Traystman, and E. Bucci Effect of cross-linked hemoglobin transfusion on endothelial-dependent dilation in cat pial arterioles Am J Physiol Heart Circ Physiol, October 1, 1998; 275(4): H1313 - H1321. [Abstract] [Full Text] [PDF]

				A. S. Rudolph, A. Sulpizio, P. Hieble, V. Macdonald, M. Chavez, and G. Feuerstein Liposome encapsulation attenuates hemoglobin-induced vasoconstriction in rabbit arterial segments J Appl Physiol, June 1, 1997; 82(6): 1826 - 1835. [Abstract] [Full Text] [PDF]

				P. Collins, G. M. C. Rosano, P. M. Sarrel, L. Ulrich, S. Adamopoulos, C. M. Beale, J. G. McNeill, and P. A. Poole-Wilson 17ß-Estradiol Attenuates Acetylcholine-Induced Coronary Arterial Constriction in Women but Not Men With Coronary Heart Disease Circulation, July 1, 1995; 92(1): 24 - 30. [Abstract] [Full Text]

				T. J. Spyt, K. L. Blake, P. A. C. Watt, and H. Thurston Inhibition of Endothelium-Dependent Relaxation by Free Hemoglobin in the Human Internal Thoracic Artery Vascular and Endovascular Surgery, January 1, 1994; 28(1): 1 - 6. [Abstract] [PDF]