Am. J. Respir. Crit. Care Med., Volume 159, Number 4, April 1999, 1125-1133

Assessment of Nitric Oxide Formation During Exercise

CLAUDETTE M. ST. CROIX, THOMAS J. WETTER, DAVID F. PEGELOW, KEITH C. MEYER, and JEROME A. DEMPSEY

Department of Preventive Medicine, University of Wisconsin-Madison, Madison, Wisconsin

We measured the end-tidal plateau in exhaled NO concentration (CETNO) by chemiluminescence and calculated the product of E and CETNO ( NO) in nine healthy subjects at rest and during three intensities of cycling exercise (30%, 60%, and 90% O₂max), two levels of hyperventilation ( E = 42.8 ± 9.1 L/min and 84.2 ± 6.6 L/min), and during breathing of hypoxic gas mixtures (five subjects, FI_O2 = 14%) at rest and during exercise at 90% O₂max. Immediately after each trial we also measured exhaled [NO] at constant expiratory flow rates ([NO]_CF) of 46 ml/s and 950 ml/s, utilizing added expiratory resistance to increase mouth pressure and close the velum (Silkoff and colleagues, Am. J. Respir. Crit. Care Med. 1997;155:260). CETNO decreased and NO increased above resting levels with increasing exercise intensity during hyperventilation and during hypoxic exercise (p < 0.05). [NO]_CF, measured at either 46 ml/s or 950 ml/s, did not increase under any of the conditions investigated (exercise, hyperventilation, or hypoxia). Venous blood from seven of the subjects was sampled for the measurement of plasma [NO₃]. Resting plasma [NO₃] averaged 42.5 ± 14.7 µmol/L, with no change during exercise, hyperventilation, or hypoxia. On the basis of these results we conclude that reported increases in NO do not reflect an exercise-induced augmentation of systemic and/or airway NO production. Rather, the increases in NO during exercise or hyperventilation are a function of high airflow rates, which reduce the luminal [NO]. This decreases the concentration gradient for NO between the alveolar space and pulmonary capillary blood, which results in a decrease in the fraction of NO taken up by the blood and an increase in the volume of NO recovered in the exhaled air ( NO). St. Croix CM, Wetter TJ, Pegelow DF, Meyer KC, Dempsey JA. Assessment of nitric oxide formation during exercise.

This article has been cited by other articles:

				H.-W. Shin, C. D. Schwindt, A. S. Aledia, C. M. Rose-Gottron, J. K. Larson, R. L. Newcomb, D. M. Cooper, and S. C. George Exercise-induced bronchoconstriction alters airway nitric oxide exchange in a pattern distinct from spirometry Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2006; 291(6): R1741 - R1748. [Abstract] [Full Text] [PDF]

				ATS Workshop Proceedings: Exhaled Nitric Oxide and Nitric Oxide Oxidative Metabolism in Exhaled Breath Condensate. Proceedings of the ATS, January 1, 2006; 3(2): 131 - 145. [Full Text] [PDF]

				E. West, M. Skowronski, A. C. MS, and E. R. McFadden Jr The Effects of Hyperpnea on Exhaled Nitric Oxide Synthesis in Normal Subjects Chest, November 1, 2005; 128(5): 3316 - 3321. [Abstract] [Full Text] [PDF]

				H. C. Haverkamp, J. A. Dempsey, J. D. Miller, L. M. Romer, D. F. Pegelow, J. R. Rodman, and M. W. Eldridge Gas exchange during exercise in habitually active asthmatic subjects J Appl Physiol, November 1, 2005; 99(5): 1938 - 1950. [Abstract] [Full Text] [PDF]

				J. A. Adams, J. Bassuk, D. Wu, M. Grana, P. Kurlansky, and M. A. Sackner Periodic acceleration: effects on vasoactive, fibrinolytic, and coagulation factors J Appl Physiol, March 1, 2005; 98(3): 1083 - 1090. [Abstract] [Full Text] [PDF]

				J. M. Hare, G. C. Nguyen, A. F. Massaro, J. M. Drazen, L. W. Stevenson, W. S. Colucci, J. C. Fang, W. Johnson, M. M. Givertz, and C. Lucas Exhaled nitric oxide: a marker of pulmonary hemodynamics in heart failure J. Am. Coll. Cardiol., September 18, 2002; 40(6): 1114 - 1119. [Abstract] [Full Text] [PDF]

				T. J. Wetter, Z. Xiang, D. A. Sonetti, H. C. Haverkamp, A. J. Rice, A. A. Abbasi, K. C. Meyer, and J. A. Dempsey Role of lung inflammatory mediators as a cause of exercise-induced arterial hypoxemia in young athletes J Appl Physiol, July 1, 2002; 93(1): 116 - 126. [Abstract] [Full Text] [PDF]

				A. TERADA, T. FUJISAWA, K. TOGASHI, T. MIYAZAKI, H. KATSUMATA, J. ATSUTA, K. IGUCHI, H. KAMIYA, and H. TOGARI Exhaled Nitric Oxide Decreases during Exercise-induced Bronchoconstriction in Children with Asthma Am. J. Respir. Crit. Care Med., November 15, 2001; 164(10): 1879 - 1884. [Abstract] [Full Text] [PDF]

				M. R. Bonsignore, G. Morici, L. Riccobono, G. Insalaco, A. Bonanno, M. Profita, A. Paterno, C. Vassalle, A. Mirabella, and A. M. Vignola Airway inflammation in nonasthmatic amateur runners Am J Physiol Lung Cell Mol Physiol, September 1, 2001; 281(3): L668 - L676. [Abstract] [Full Text] [PDF]

				T. J. Wetter, C. M. St. Croix, D. F. Pegelow, D. A. Sonetti, and J. A. Dempsey Effects of exhaustive endurance exercise on pulmonary gas exchange and airway function in women J Appl Physiol, August 1, 2001; 91(2): 847 - 858. [Abstract] [Full Text] [PDF]

				O. E. Suman and K. C. Beck Role of nitric oxide during hyperventilation-induced bronchoconstriction in the guinea pig J Appl Physiol, April 1, 2001; 90(4): 1474 - 1480. [Abstract] [Full Text] [PDF]

				H. W. F. M. De Gouw, S. J. Marshall-Partridge, H. Van der Veen, J. G. Van den Aardweg, P. S. Hiemstra, and P. J. Sterk Role of nitric oxide in the airway response to exercise in healthy and asthmatic subjects J Appl Physiol, February 1, 2001; 90(2): 586 - 592. [Abstract] [Full Text] [PDF]

				E. Clini, L. Bianchi, M. Vitacca, R. Porta, K. Foglio, and N. Ambrosino Exhaled Nitric Oxide and Exercise in Stable COPD Patients Chest, March 1, 2000; 117(3): 702 - 707. [Abstract] [Full Text] [PDF]