EFFECTS OF DIFFERENT EXPOSURE TIMES TO TOBACCO-SMOKE INTOXICATION ON CARBOXYHEMOGLOBIN AND HEPATIC ENZYMATE ACTIVITIES IN MICE

The aim of this work was to determine the effects of different exposur e times to smoke on carboxyhemoglobin (HbCO) and hepatic enzymate acti vities in order to adapt a tobacco smoke intoxication model in mice. M ice were exposed to tobacco smoke for various durations of either 2 (g roup S2), 4 (group S4), 8 (group S8), or 31 days (group S31) using the Hamburg II machine. Controls (nonexposed animals) were used under the same experimental conditions. On the 2nd, 4th, 8th, and 31st day, mic e were sacrificed by decapitation, and blood carboxyhemoglobin level a nd hepatic enzymate activities catalysed by CYP 450 families were meas ured. Our data with regard to the exposed group indicated first that H bCO was significantly increased after 4 or 8 days of exposure and decr eased after 31 days compared to controls (where HbCO was constant for the duration of the 31 days) and second, the enzymate activities were significantly higher during the period of exposure. In conclusion, a 4 - and 8-day exposure period with eight cigarettes per day seems to be the model of tobacco smoke intoxication in mice to be chosen.