Adventitial alterations are the main features in pulmonary artery remodeling due to long-term chronic intermittent hypobaric hypoxia in rats.
Long-term chronic intermittent exposure to altitude hypoxia is a labor phenomenon requiring further research. Using a rat model, we examined whether this type of exposure differed from chronic exposure in terms of pulmonary artery remodeling and other features. Rats were subjected to chronic hypoxia (CH, n = 9) and long-term intermittent hypoxia (CIH2x2; 2 days of hypoxia/2 days of normoxia, n = 10) in a chamber (428 Torr, 4,600 m of altitude) for 46 days and compared to rats under normoxia (NX, n = 10). Body weight, hematocrit, and right ventricle ratio were measured. Pulmonary artery remodeling was assessed using confocal microscopy of tissues stained with a nuclear dye (DAPI) and CD11b antibody. Both hypoxic conditions exhibited increased hematocrit and hypertrophy of the right ventricle, tunica adventitia, and tunica media, with no changes in lumen size. The medial hypertrophy area (larger in CH) depicted a significant increase in smooth muscle cell number. Additionally, CIH2x2 increased the adventitial hypertrophy area, with an increased cellularity and a larger prevalence of clustered inflammatory cells. In conclusion, CIH2x2 elicits milder effects on pulmonary artery medial layer muscularization and subsequent right ventricular hypertrophy than CH. However, CIH2x2 induces greater and characteristic alterations of the adventitial layer.
Institute of Health Studies, Universidad Arturo Prat, Avenue Arturo Prat 2120, 11100939 Iquique, Chile.
Julio
J
Brito
Institute of Health Studies, Universidad Arturo Prat, Avenue Arturo Prat 2120, 11100939 Iquique, Chile.
Patricia
P
Siques
Department of Physiology, Faculty of Medicine, Universidad Autónoma de Madrid, c/Arzobispo Morcillo 2, 28029 Madrid, Spain.
Silvia M
SM
Arribas
Department of Physiology, Faculty of Medicine, Universidad Autónoma de Madrid, c/Arzobispo Morcillo 2, 28029 Madrid, Spain.
Angel L
AL
López de Pablo
Department of Physiology, Faculty of Medicine, Universidad Autónoma de Madrid, c/Arzobispo Morcillo 2, 28029 Madrid, Spain.
M Carmen
MC
González
Institute of Health Studies, Universidad Arturo Prat, Avenue Arturo Prat 2120, 11100939 Iquique, Chile.
Nelson
N
Naveas
Institute of Health Studies, Universidad Arturo Prat, Avenue Arturo Prat 2120, 11100939 Iquique, Chile.
Karem
0000-0003-1498-5579
K
Arriaza
Institute of Health Studies, Universidad Arturo Prat, Avenue Arturo Prat 2120, 11100939 Iquique, Chile.
Karen
K
Flores
Department of Biological and Physiological Sciences, Faculty of Sciences and Philosophy/IIA, Universidad Peruana Cayetano Heredia, Avenue Honorario Delgado 430, Urb. Ingenieria, Distrito, Lima 31, Peru.
Fabiola
F
León-Velarde
Institute of Health Studies, Universidad Arturo Prat, Avenue Arturo Prat 2120, 11100939 Iquique, Chile.
Ruth
R
Pulido
Institute of Health Studies, Universidad Arturo Prat, Avenue Arturo Prat 2120, 11100939 Iquique, Chile.
Stefany
S
Ordenes
Department of Preventive Medicine and Public Health, Faculty of Medicine, Universidad Autónoma de Madrid, c/Arzobispo Morcillo 2, 28029 Madrid, Spain.
M Rosario
MR
López
D063194:Adventitia / Q000473:pathology / Q000503:physiopathology; D000532:Altitude Sickness / Q000473:pathology / Q000503:physiopathology; D000818:Animals; D004195:Disease Models, Animal; D000860:Hypoxia / Q000473:pathology / Q000503:physiopathology; D011651:Pulmonary Artery / Q000473:pathology / Q000503:physiopathology; D051381:Rats; D017208:Rats, Wistar; D066253:Vascular Remodeling