Changes in the airway resistance to histamine in each group.

Rats were treated with aerosolized saline or increasing doses of histamine. Airway resistance was calculated as the index of percent increase in airway resistance when compared with the peak of the reaction with baseline. The values were expressed ±s (n = 8). * indicates significant difference as compared with the control group (P<0.05); # indicates significant difference between s-asthma and asthma groups (P<0.05).