EFFECTS OF ACUTE CIGARETTE-SMOKE EXPOSURE ON MACROPHAGE KINETICS AND RELEASE OF TUMOR-NECROSIS-FACTOR-ALPHA IN RATS

SOME biological parameters before and after an acute episode of cigare tte smoking in rats have been evaluated. The carboxyhaemoglobin levels depended either on the number of cigarettes, or on the time of exposu re to cigarette smoke and returned to pre-smoking values in about 2 h. The evaluation of the kinetics of alveolar and peritoneal macrophages in rats after a smoking session of three cigarettes within an hour, i ndicated that alveolar macrophages in the bronchoalveolar lavage fluid significantly increased 8 h after the smoking, whereas the number of peritoneal macrophages remained practically constant. The incubation o f these cells for various times at 37-degrees-C in a humidified atmosp here, resulted in a spontaneous release, 24 h thereafter, of variable amounts of tumour necrosis factor alpha (TNFalpha), which remained pra ctically constant during the following days. Neither alveolar macropha ges of control rats, nor peritoneal macrophages of both control and sm oking rats were able to release TNFalpha. Moreover, after lipopolysacc haride induction of alveolar macrophages of both control and smoking r ats, an increased release of TNFalpha was observed, indicating that th ese cells were in an active state.