ABSTRACT Susceptible individuals with asthma and rhinitis report exacerbations with exposure to air fresheners. Experimental models may help shed light on the mechanism. We hypothesized mice will have increased bronchial reactivity after a period of air freshener exposure. Two strains of 25-30 gm 10-week-old male mice (C57BL/6J and BALB/cByJ) were exposed to an over-the-counter air freshener for 45 days, then mice were anesthetized and intubated by surgical tracheostomy. Newtonian resistances (Rn) were measured at baseline, after challenge with phosphate buffered saline (PBS) and acetylcholine (ACh) using FlexiVent. Statistical analysis was performed comparing means by student’s t-test. ACh challenge resulted in increased Rn in air freshener-exposed BALB/cByJ mice compared to controls. In the C57BL/6J strain, the mean Rn in mice exposed to air freshener was 0.62 ± 0.21 cmH2O/mL/sec versus 0.50 ± 0.08 in controls: p = 0.11. For the BALB/cByJ strain, the difference was 0.96 ± 0.26 cmH2O/mL/sec in air freshener-exposed versus 0.62 ± 0.28 cmH2O/mL/sec in controls: p = 0.02. BALB/cByJ mice had significantly higher Rn than C57BL/6J mice (p = 0.04) after ACh challenge. A mouse model of air freshener exposure may be used to study bronchial hyper-reactivity from exposure to air fresheners. Mouse strain is an important consideration.
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