Effect of the ROCK inhibitor fasudil on O3-induced AHR. WT mice were exposed to O3 (2 ppm for 3 h) or air. Twenty-four hours later, mice were treated with fasudil (3 or 10 mg/kg ip) or PBS, and airway responsiveness was measured. Rn (A), G (B), H (C), and RL (D). Results are means ± SE of data from 5 to 6 mice/group. *P < 0.05 vs. air-exposed mice with the same treatment; #P < 0.05 vs. PBS-treated mice with same exposure; +P < 0.05 vs. 3 mg/kg.