2. Subjects may be enrolled with mild asthma if they have an FEV1 of at least 80% of predicted and FEV1/FVC ratio of at least .70 (without the use of bronchodilating medications for 12 hours). This is consistent with lung function of persons with mild episodic or mild persistent asthma. For the purpose of this protocol, an asthmatic individual will be defined as having: a) a positive methacholine challenge with a provocative concentration of methacholine producing a 20% fall in FEV1 (PC20 methacholine) with less than or equal to 10 mg/ml by the method used; OR b) physician diagnosed asthma with symptoms and chronic daily therapy consistent with mild asthma.