The effect of maternal exposure to MCP230 on the development of AHR in offspring. AHR to Mch was assessed 48 h after the final aerosol challenge. Results are expressed as airway resistance in mice exposed to nebulized Mch. Individual responses were normalized to their perspecitve baseline (0 mg/ml Mch) and are expressed as normalized means ± SEM (n =6-10/group). *p < 0.05.