Journal of Applied Physiology, Vol 62, Issue 3 1155-1159, Copyright © 1987 by American Physiological Society

ARTICLES

Airway reactivity in infants: a positive response to methacholine and metaproterenol

R. S. Tepper

Because the presence of bronchial smooth muscle reactivity in infants remains controversial, airway reactivity was assessed in 10 normal, asymptomatic male infants less than 15 mo of age by measuring the changes that occurred in the maximal expiratory flows at functional residual capacity (VmaxFRC) during a methacholine bronchial challenge test. Sleeping infants inhaled doubling concentrations of methacholine by 2 min of tidal breathing, starting with a concentration of 0.075 mg/ml, and the bronchial challenge was stopped when VmaxFRC decreased by at least 40%. The threshold concentration of methacholine required to produce a decrease in VmaxFRC by 2 SD's of the control value was 0.43 mg/ml (0.11-0.90). By a methacholine concentration of 1.2 mg/ml, all infants decreased VmaxFRC by at least 40% (range 40-75%), and the mean dose required to produce a 40% decrease was 0.72 mg/ml. The airway reactivity was not related to base-line flows. During the methacholine challenge, no infant developed wheezing, but the percent oxygen saturation for the group decreased significantly (P less than 0.05) from 94 to 92%. Following the methacholine, the infants inhaled the bronchodilator metaproterenol, and 10 min later, VmaxFRC returned to base line. This study demonstrates that infants exhibit airway reactivity as evidenced by bronchoconstriction with methacholine and the subsequent bronchodilation with metaproterenol.

This article has been cited by other articles:

				Z. Xue, L. Zhang, Y. Liu, S. J. Gunst, and R. S. Tepper Chronic inflation of ferret lungs with CPAP reduces airway smooth muscle contractility in vivo and in vitro J Appl Physiol, March 1, 2008; 104(3): 610 - 615. [Abstract] [Full Text] [PDF]

				Diagnosis of asthma Can. Med. Assoc. J., September 13, 2005; 173(6_suppl): S15 - S19. [Full Text] [PDF]

				H. B. Panitch The Role of Pulmonary Function Testing in Infants NeoReviews, May 1, 2004; 5(5): e183 - e185. [Full Text] [PDF]

				R. Ramchandani, X. Shen, S. J. Gunst, and R. S. Tepper Comparison of elastic properties and contractile responses of isolated airway segments from mature and immature rabbits J Appl Physiol, July 1, 2003; 95(1): 265 - 271. [Abstract] [Full Text] [PDF]

				A. Weist, T. Williams, J. Kisling, C. Clem, and R. S. Tepper Volume history and effect on airway reactivity in infants and adults J Appl Physiol, September 1, 2002; 93(3): 1069 - 1074. [Abstract] [Full Text] [PDF]

				R. K. Lambert, R. Ramchandani, X. Shen, S. J. Gunst, and R. S. Tepper Computational model of airway narrowing: mature vs. immature rabbit J Appl Physiol, August 1, 2002; 93(2): 611 - 619. [Abstract] [Full Text] [PDF]

				C. DELACOURT, M.-R. BENOIST, S. WAERNESSYCKLE, P. RUFIN, J.-J. BROUARD, J. DE BLIC, and P. SCHEINMANN Relationship between Bronchial Responsiveness and Clinical Evolution in Infants Who Wheeze . A Four-Year Prospective Study Am. J. Respir. Crit. Care Med., October 15, 2001; 164(8): 1382 - 1386. [Abstract] [Full Text] [PDF]

				A. B. GOLDSTEIN, R. G. CASTILE, S. D. DAVIS, D. A. FILBRUN, R. L. FLUCKE, K. S. McCOY, and R. S. TEPPER Bronchodilator Responsiveness in Normal Infants and Young Children Am. J. Respir. Crit. Care Med., August 1, 2001; 164(3): 447 - 454. [Abstract] [Full Text] [PDF]

				R. Saga, H. Mochizuki, K. Tokuyama, and A. Morikawa Relationship Between Bronchial Hyperresponsiveness and Development of Asthma in Wheezy Infants Chest, March 1, 2001; 119(3): 685 - 690. [Abstract] [Full Text] [PDF]

				B. Niggemann, S. Illi, C. Madloch, K. Volkel, S. Lau, R. Bergmann, E. von Mutius, U. Wahn, and MAS-Study Group Histamine challenges discriminate between symptomatic and asymptomatic children Eur. Respir. J., February 1, 2001; 17(2): 246 - 253. [Abstract] [Full Text] [PDF]

				G L Hall, Z Hantos, J H Wildhaber, F Peták, and P D Sly Methacholine responsiveness in infants assessed with low frequency forced oscillation and forced expiration techniques Thorax, January 1, 2001; 56(1): 42 - 47. [Abstract] [Full Text]

				H. Mochizuki, M. Shigeta, H. Arakawa, M. Kato, K. Tokuyama, and A. Morikawa Bronchial Hyperresponsiveness Before and After the Diagnosis of Bronchial Asthma in Children Pediatrics, December 1, 2000; 106(6): 1442 - 1446. [Abstract] [Full Text]

				A. L. Mansell, A. L. McAteer, and E. H. Oldmixon Mechanical dissociation of bronchi from parenchyma in the immature piglet lung J Appl Physiol, July 1, 2000; 89(1): 228 - 234. [Abstract] [Full Text] [PDF]

				M. H. JONES, S. D. DAVIS, J. A. KISLING, J. M. HOWARD, R. CASTILE, and R. S. TEPPER Flow Limitation in Infants Assessed by Negative Expiratory Pressure Am. J. Respir. Crit. Care Med., March 1, 2000; 161(3): 713 - 717. [Abstract] [Full Text] [PDF]

				M. JONES, R. CASTILE, S. DAVIS, J. KISLING, D. FILBRUN, R. FLUCKE, A. GOLDSTEIN, C. EMSLEY, W. AMBROSIUS, and R. S. TEPPER Forced Expiratory Flows and Volumes in Infants . Normative Data and Lung Growth Am. J. Respir. Crit. Care Med., February 1, 2000; 161(2): 353 - 359. [Abstract] [Full Text]

				P. M. RENZI, J. P. TURGEON, J. E. MARCOTTE, S. P. DRBLIK, D. BERUBE, M. F. GAGNON, and S. SPIER Reduced Interferon-gamma Production in Infants with Bronchiolitis and Asthma Am. J. Respir. Crit. Care Med., May 1, 1999; 159(5): 1417 - 1422. [Abstract] [Full Text] [PDF]

				C. Delacourt, M.-R. Benoist, S. Waernessyckle, P. Rufin, J.-J. Brouard, J. de Blic, and P. Scheinmann Repeatability of lung function tests during methacholine challenge in wheezy infants Thorax, November 1, 1998; 53(11): 933 - 938. [Abstract] [Full Text]

				W. W. BUSSE, S. P. BANKS-SCHLEGEL, and G. L. LARSEN Effects of Growth and Development on Lung Function . Models for Study of Childhood Asthma Am. J. Respir. Crit. Care Med., July 1, 1997; 156(1): 314 - 319. [Full Text]

				P. K. JEFFERY The Development of Large and Small Airways Am. J. Respir. Crit. Care Med., May 1, 1997; 157(5): 174 - 180. [Full Text]

				M. J. HAYDEN, F. PETAK, Z. HANTOS, G. HALL, and P. D. SLY Using Low-frequency Oscillation to Detect Bronchodilator Responsiveness in Infants Am. J. Respir. Crit. Care Med., February 1, 1997; 157(2): 574 - 579. [Abstract] [Full Text]