Previously we have reported that association of cigarette smoke (CS) and chronic hypoxia (CH) interact
positively to physiopathologically remodel pulmonary circulation. In present study we have exposed
guinea pigs to CS smoke (four cigarettes/day; 3 months; CS) and to chronic hypoxia (12% O2, 15 days;
CH) alone or in combination (CSCH animals) and evaluated airways remodeling and resistance assessed
as Penh (enhance pause). We measured Penh while animals breathe air, 10% O2 and 5% CO2 and found
that CS and CH animals have higher Penh than controls; Penh was even larger in CSCH animals. A rough
parallelism between Penh and thickness of bronchiolar wall and muscular layer and Goblet cell number
was noticed. We conclude that CS and CH association accelerates CS-induced respiratory system damage,
evidenced by augmented airway resistance, bronchial wall thickness and muscularization and Goblet
cell number. Our findings would suggest that appearance of hypoxia would aggravate any preexisting
pulmonary pathology by increasing airways resistance and reactivity.
