Aspects of the immunotoxicity of chronic tobacco smoke exposure of the rat.
One hundred and eighty Wistar-strain rats were exposed to differing concentrations of tobacco smoke, for periods of up to 20 months, in order to examine the response of the pulmonary immune system. The amount of bronchus-associated lymphoid tissue (BALT) in the lungs of exposed rats increased initially over the first 5 weeks of exposure, subsequently falling to below control levels by the fourteenth week and eventually increasing again to a level slightly higher than that of the controls by the twelfth month, at which level it was maintained until the twentieth month. Quantitative immunohistochemical assay of bronchial immunoglobulin levels (only assessed over the initial 14 weeks of exposure) revealed a transitory enhancement of levels followed by a depression, the speed of response being apparently dose-related. Alveolar macrophage activity, indicated by lysosomal enzyme activity, increased relative to the control animals over the same 14-week exposure period. The significance of these observations is discussed and a tentative explanatory hypothesis is advanced.
D000818:Animals; D002455:Cell Division; D005260:Female; D007136:Immunoglobulins / Q000032:analysis; D007365:Intercellular Junctions; D008168:Lung / Q000276:immunology*; D008214:Lymphocytes; D008264:Macrophages / Q000276:immunology; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D014028:Tobacco Smoke Pollution
D007136:Immunoglobulins; D014028:Tobacco Smoke Pollution