Fig. 1.

Protocol used to develop allergic model and treatment groups. Mice were divided into control (CON) and allergen sensitized (SEN) groups. Mice were sensitized with ovalbumin (OVA) on day 1 and 6 (25–30 μg; i.p.), followed by 5% OVA aerosol challenge (days 11–13) to obtain the SEN group. For limonene-treated groups, the mice were first exposed to aerosolized 0.01% (v/v) limonene solution (7.5 ml) for 20 min followed by OVA aerosol challenges