Ultrastructural alterations during embryonic rats' lung development caused by ozone.
Ozone (O3) is an oxidizing agent that acts on phospholipids, proteins and sugars of cellular membranes producing free radicals, which cause oxidative damages. The O3 exposure has been used as a model to study oxidative stress, in which the respiratory airways represent the entrance to the organism. In this study, ultrastructural alterations were identified at the bronchiolar level during the intra-uterine lung development, using an O3 exposure model in pregnant rats during 18, 20 and 21 days of gestation. Twelve pregnant Wistar rats, six controls and six exposed to 1 ppm O3 inhalation during 12 h per day, were used. The rats were sacrificed at gestational days 18, 20 and 21; the fetuses were obtained and their lungs dissected. The ultrastructural analysis evidenced swollen mitochondria, cytoplasmic vacuolization of the epithelial cells and structural disorder caused by the oxidative stress. At gestation day 20, flake-off epithelial cells and laminar bodies in the bronchiolar lumen were observed. In the 21-gestation-day group, the mitochondria were edematous and their cristae were disrupted by the damage caused in mitochondrial membranes.
López
Irma
I
Departamento de Biologia Celular y Tisular, Facultad de Medicina UNAM, Edificio A tercer piso, CP 04510, México City, Mexico. irmelen@servidor.unam.mx
Sánchez
Ivonne
I
Bizarro
Patricia
P
Acevedo
Sandra
S
Ustarroz
Martha
M
Fortoul
Teresa
T
D000818:Animals; D001980:Bronchi / Q000648:ultrastructure; D019570:Inhalation Exposure; D008171:Lung Diseases / Q000139:chemically induced* / Q000473:pathology; D010126:Ozone / Q000633:toxicity*; D011650:Pulmonary Alveoli / Q000187:drug effects; D051381:Rats / Q000196:embryology*; D017208:Rats, Wistar
D010126:Ozone