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 enviro nmental stress has not been examined extensively. In this study, the p roduction of stress-inducible HSP 70 in the ferret lung was examined f ollowing repeated inhalant exposure to two concentrations of sidestrea m cigarette smoke: (a) 11.23 +/- 0.75 (SEM) mg/m(3) and (b) 1.62 +/- 0 .30 mg/m(3). Ferrets (n = 5 for each concentration) starting at 5 wk o f 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 fe rrets (n = 2) were exposed twice for 2 h in a single day Co filtered a ir for a total of 4 h while corresponding ferrets (n = 5 for each ciga rette 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 perip heral 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 a nalysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis ( SDS-PAGE), protein immunoblotting, and subsequent chemiluminescence de tection. Results revealed that stress-inducible HSP 70 is present cons titutively in the control ferret lung and is not elevated significantl y in lungs from either repeated sidestream smoke-exposed ferrets (p = .9002) or acute smoke-exposed ferrets (p = .5473). Specifically, in th e chronic study the means (optical density units) +/- SD for stress-in ducible 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) war 82.72 +/- 13.29; for the smoke-exposed animals (n = 10), the corresponding mean was 85.00 +/- 8.35 optical density units.