Responses of rat alveolar macrophages to inhaled brass powder.
The effects of a single acute exposure to inhaled brass dust on rat pulmonary alveolar macrophages (PAM) were determined. Pulmonary alveolar macrophages lavaged from the lungs of these experimental animals showed both morphological and functional abnormalities. Exposure to brass dust caused a rapid, transient inflammatory response, producing an influx of polymorphonuclear leukocytes into the lavage fluid. Binucleation and multinucleation of PAM were sensitive morphological indicators of pulmonary stress that persisted throughout the 14-day course of the experiment. Pulmonary alveolar macrophages from rats exposed to brass dust were phagocytically activated; both the total numbers of test particulates ingested and the phagocytic index were elevated. Chemotaxis, as measured by direct cellular migration in Boyden chambers, was inhibited for 3 days after exposure, but was markedly stimulated from 7 to 14 days. This was interpreted as a possible consequence of a selective release of lymphokines during the course of the inflammatory response. Some of these results, based on in vivo exposure of PAM to inhaled particulates, differ from those derived from in vitro exposure. This points to the fact that it is virtually impossible to duplicate the native chemical microenvironment of PAM in vitro and emphasizes the necessity of bringing about PAM-particle interactions in the intact lung in order to obtain more physiologically relevant data.
Anderson
R S
RS
U.S. Army Chemical Research, Development and Engineering Center, Aberdeen Proving Ground, MD 21010-5423.
Gutshall
L L
LL
Thomson
S A
SA
D000280:Administration, Inhalation; D000393:Air Pollutants / Q000633:toxicity; D000497:Alloys / Q000633:toxicity*; D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000032:analysis; D002452:Cell Count / Q000187:drug effects; D002633:Chemotaxis / Q000187:drug effects; D003300:Copper / Q000633:toxicity*; D004391:Dust / Q000009:adverse effects*; D008264:Macrophages / Q000187:drug effects / Q000276:immunology* / Q000473:pathology; D008297:Male; D010587:Phagocytosis / Q000187:drug effects; D011650:Pulmonary Alveoli / Q000187:drug effects / Q000276:immunology* / Q000473:pathology; D051381:Rats; D011919:Rats, Inbred Strains; D015032:Zinc / Q000633:toxicity*
D000393:Air Pollutants; D000497:Alloys; D004391:Dust; C048399:brass; D003300:Copper; D015032:Zinc