EFFECTS OF REPEATED SIDESTREAM CIGARETTE SMOKE INHALATION ON STRESS-INDUCIBLE HEAT SHOCK PROTEIN 70 IN THE FERRET LUNG

In vivo expression of lung heat shock proteins (HSPs) following environmental stress has not been examined extensively. In this study, the production of stress-inducible HSP 70 in the ferret lung was examined following repeated inhalant exposure to two concentrations of 3 3 sidestream cigarette smoke: (a) 11.23 0.75 (SEM) mg/m and (b) 1.62 0.30 mg/m. Ferrets (n = 5 for each concentration) starting at 5 wk of age were exposed head-only to cigarette smoke for 2 h/day, 5 days/wk for a total of 15 wk; in the acute exposures, control adult female ferrets (n = 2) were exposed twice for 2 h in a single day to filtered air for a total of 4 h while corresponding ferrets (n = 5 for each cigarette smoke concentration) were exposed twice for 2 h in a single day for a total of 4 h to sidestream cigarette smoke. Samples of the peripheral lung from the right apical lobe of the 5-wk-old ferrets and from the right middle lobe of the adult female ferrets were obtained for analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), protein immunoblotting, and subsequent chemiluminescence detection. Results revealed that stress-inducible HSP 70 is present constitutively in the control ferret lung and is not elevated significantly in lungs from either repeated sidestream smoke-exposed ferrets (p = .9002) or acute smokeexposed ferrets (p = .5473). Specifically, in the chronic study the means (optical density units) SD for stress-inducible HSP 70 were 78.00 17.18 and 75.60 14.64, respectively, for high and low smoke levels in comparison to the mean of 85.50 12.09 in the control air-exposed animals. In the acute study, the mean (optical density units) SD for the control air-exposed animals (n = 2) was 82.72 13.29; for the smoke-exposed animals (n = 10), the corresponding mean was 85.00 8.35 optical density units.