title: A model of pulmonary atelectasis in rats: activation of alveolar macrophage and cytokine release.
abstract: Although atelectasis frequently occurs after surgery and trauma, and such patients have elevated body temperatures, the mechanism of temperature elevation secondary to atelectasis is unknown. Moreover, a small animal model has not been available to study the pathophysiology of pulmonary atelectasis. The purpose of this study, therefore, was to develop a model of pulmonary atelectasis in rats. Because interleukin-1 (IL-1) and tumor necrosis factor (TNF), both potent pyrogens, are produced by macrophages during infection and inflammation, our aim was also to determine whether alveolar macrophages produce IL-1 or TNF in response to atelectasis. Whole-lung atelectasis was produced in rats by ligating the left main stem bronchus while maintaining ventilation of the right lung. After a 1-h period of atelectasis, alveolar macrophages were harvested from the right and left lungs and incubated for 24 h, and the supernatants were assayed for IL-1 and TNF. Both IL-1 and TNF levels of macrophage cultures from the atelectatic lung were significantly increased compared with the control lung. These results suggest that increased IL-1 or TNF production by alveolar macrophages may be responsible for fever caused by atelectasis.
authors.affiliation: Department of Surgery, Michigan State University, East Lansing 48824.
authors.forename: J M
authors.initials: JM
authors.lastname: Kisala
authors.forename: A
authors.initials: A
authors.lastname: Ayala
authors.forename: R N
authors.initials: RN
authors.lastname: Stephan
authors.forename: I H
authors.initials: IH
authors.lastname: Chaudry
mesh_terms: D000818:Animals; D007375:Interleukin-1 / Q000096:biosynthesis*; D008262:Macrophage Activation / Q000502:physiology*; D016676:Macrophages, Alveolar / Q000502:physiology*; D008297:Male; D010100:Oxygen / Q000097:blood; D001261:Pulmonary Atelectasis / Q000473:pathology / Q000503:physiopathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
chemical_list: D007375:Interleukin-1; D014409:Tumor Necrosis Factor-alpha; D010100:Oxygen