Chronic Hypoxia Accentuates Dysanaptic Lung Growth
| Autor: | Natasha M. Krowchuk, Miranda Kirby, Robert S. Tepper, Ana Stok, Federico Bonilla, María M. Caram, Harvey O. Coxson, Pedro T. Grassino, Conrado J. Llapur, Myriam R. Martínez, Héctor H. Altieri |
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| Rok vydání: | 2016 |
| Předmět: |
Adult
Male Pulmonary and Respiratory Medicine medicine.medical_specialty Pathology Argentina Lumen (anatomy) 030204 cardiovascular system & hematology Critical Care and Intensive Care Medicine 03 medical and health sciences 0302 clinical medicine Altitude Forced Expiratory Volume Internal medicine Tidal Volume medicine Humans Lung volumes Hypoxia Lung business.industry Organ Size respiratory system Chronic hypoxia Respiratory Function Tests respiratory tract diseases Lung density medicine.anatomical_structure 030228 respiratory system Spirometry Pulmonary diffusion Cardiology Female Tomography X-Ray Computed Airway business |
| Zdroj: | American Journal of Respiratory and Critical Care Medicine. 194:327-332 |
| ISSN: | 1535-4970 1073-449X |
| DOI: | 10.1164/rccm.201509-1851oc |
| Popis: | Adults born and raised at high altitudes have larger lung volumes and greater pulmonary diffusion capacity compared with adults at low altitude; however, it remains unclear whether the air and tissue volumes have comparable increases and whether there is a difference in airway size.To assess the effect of chronic hypoxia on lung growth using in vivo high-resolution computed tomography measurements.Healthy adults born and raised at moderate altitude (2,000 m above sea level; n = 19) and at low altitude (400 m above sea level; n = 23) underwent high-resolution computed tomography. Differences in total lung, air, and tissue volume, mean lung density, as well as airway lumen and wall areas in anatomically matched airways were compared between groups.No significant differences for age, sex, weight, or height were found between the two groups (P 0.05). In a multivariate regression model, altitude was a significant contributor for total lung volume (P = 0.02), air volume (P = 0.03), and tissue volume (P = 0.03), whereby the volumes were greater for the moderate- versus the low-altitude group. However, altitude was not a significant contributor for mean lung density (P = 0.35) or lumen and wall areas in anatomically matched segmental, subsegmental, and subsubsegmental airways.Our findings suggest that the adult lung did not increase lung volume later in life by expansion of an existing number of alveoli, but rather from increased alveolarization early in life. In addition, chronic hypoxia accentuates dysanaptic lung growth by increasing the lung parenchyma but not the airways. |
| Databáze: | OpenAIRE |
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