|
|
||||||||
Pediatric Heart Lung Center and Department of Pediatrics, University of Colorado School of Medicine, Denver, Colorado
Submitted 30 July 2004 ; accepted in final form 23 November 2004
Persistent pulmonary hypertension of the newborn (PPHN) is a clinical disorder characterized by abnormal vascular structure, growth, and reactivity. Disruption of vascular growth during early postnatal lung development impairs alveolarization, and newborns with lung hypoplasia often have severe pulmonary hypertension. To determine whether pulmonary hypertension can directly impair vascular growth and alveolarization in the fetus, we studied the effects of chronic intrauterine pulmonary hypertension on lung growth in fetal lambs. We performed surgery, which included partial constriction of the ductus arteriosus (DA) to induce pulmonary hypertension (PH, n = 14) or sham surgery (controls, n = 13) in fetal lambs at 112125 days (term = 147 days). Tissues were harvested near term for measurement of right ventricular hypertrophy (RVH), radial alveolar counts (RAC), mean linear intercepts (MLI), wall thickness, and vessel density of small pulmonary arteries. Chronic DA constriction caused RVH (P < 0.0001), increased wall thickness of small pulmonary arteries (P < 0.002), and reduced small pulmonary artery density (P < 0.005). PH also reduced alveolarization, causing a 27% reduction in RAC and 20% increase in MLI. Furthermore, prolonged DA constriction (21 days) not only decreased RAC and increased MLI by 30% but also caused a 25% reduction of lung-body weight ratio. We conclude that chronic PH reduces pulmonary arterial growth, decreases alveolar complexity, and impairs lung growth. We speculate that chronic hypertension impairs vascular growth, which disrupts critical signaling pathways regulating lung vascular and alveolar development, thereby interfering with alveolarization and ultimately resulting in lung hypoplasia.
lung development; angiogenesis; persistent pulmonary hypertension of the newborn; lung hypoplasia
This article has been cited by other articles:
![]() |
R.-J. Teng, A. Eis, I. Bakhutashvili, N. Arul, and G. G. Konduri Increased superoxide production contributes to the impaired angiogenesis of fetal pulmonary arteries with in utero pulmonary hypertension Am J Physiol Lung Cell Mol Physiol, July 1, 2009; 297(1): L184 - L195. [Abstract] [Full Text] [PDF] |
||||
![]() |
P.-H. Rolland, P. de Lagausie, E. Stathopoulos, O. Lepretre, G. Viudes, G. Gorincour, G. Hery, C. de Magnee, O. Paut, and J.-M. Guys Phasic hemodynamics and reverse blood flows in the aortic isthmus and pulmonary arteries of preterm lambs with pulmonary vascular dysfunction Am J Physiol Heart Circ Physiol, December 1, 2008; 295(6): H2231 - H2241. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Gien, G. J. Seedorf, V. Balasubramaniam, N. Tseng, N. Markham, and S. H. Abman Chronic intrauterine pulmonary hypertension increases endothelial cell Rho kinase activity and impairs angiogenesis in vitro Am J Physiol Lung Cell Mol Physiol, October 1, 2008; 295(4): L680 - L687. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Gien, G. J. Seedorf, V. Balasubramaniam, N. Markham, and S. H. Abman Intrauterine Pulmonary Hypertension Impairs Angiogenesis In Vitro: Role of Vascular Endothelial Growth Factor Nitric Oxide Signaling Am. J. Respir. Crit. Care Med., December 1, 2007; 176(11): 1146 - 1153. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Thebaud and S. H. Abman Bronchopulmonary Dysplasia: Where Have All the Vessels Gone? Roles of Angiogenic Growth Factors in Chronic Lung Disease Am. J. Respir. Crit. Care Med., May 15, 2007; 175(10): 978 - 985. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |