[A pathologic study on the bronchioles and lung tissues in guinea pig asthma models].
OBJECTIVE
To probe further the pathologic changes in peripheral airways and lung tissues and to observe the changes of surfactant in asthma.


METHODS
(1) The guinea pig asthma models were established with ovalbumin challenge method. (2) 6 groups were studied: control group, asthma group of day 1, asthma group of day 4, asthma group of day 14, intraperitoneal dexamethasone group, and budesonide inhalation group. (3) The pathologic changes were observed under optical and electron microscope. (4) The total and differential white blood cells counts of bronchoalveolar lavage fluid(BALF) were carried out. (5) The total amounts of phospholipids which represent the levels of pulmonary surfactant were measured with phosphorus detection method.


RESULTS
(1) Significant hyperplasia of mucous membrane, basement membrane, and smooth muscle layer of central and peripheral airways in the asthma groups were seen. The alveolar walls were significantly thickened and alveolar spaces diminished (P < 0.001, compared with the control group). Significant infiltration of eosinophils and lymphocytes were observed in airways and lung tissues. (2) The total cell number and the number eosinophils and lymphocytes in BALF were significantly increased in the asthma groups than those in the control group(P < 0.01). Neutrophils were dominant at early stage, but eosinophils and lymphocytes at late stage. (3) The ultrastructural changes of type II alveolar cells in asthma group included cell swelling, evacuation of lamellar bodies and partial cell desquamation. (4) The total amount of phospholipids in BALF was significantly decreased in the asthma groups as compared with that in the control group (P < 0.01). The above changes were significantly improved in both corticosteroid treated groups.


CONCLUSIONS
Widespread and significant inflammation with eosinophilic infiltration exists in the bronchioles and alveolar walls in guinea pig asthma models. Not only there is structural change, but also the function of alveolar cells is influenced. Asthma is a disease involving the whole airway and lung system.
Zeng
Z
Z
Department of Respiratory Diseases, The 304th Hospital of PLA, Beijing 100037, China.
Cui
D
D
Liang
Y
Y
Peng
R
R
Wang
D
D
D000818:Animals; D001249:Asthma / Q000473:pathology*; D001980:Bronchi / Q000473:pathology*; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D004195:Disease Models, Animal; D006168:Guinea Pigs; D011650:Pulmonary Alveoli / Q000473:pathology*; D011663:Pulmonary Surfactants / Q000032:analysis; D051381:Rats
D011663:Pulmonary Surfactants