ROS scavenging reduces the effect of GM or Zym.

Simultaneous Application of the ROS scavengers ACC (20 mM) and Tempol (5 mM) in the presence of GM (0.02 mg/ml) restored the Epi (10⁻⁸ M) induced PTV. This increase in PTV was significantly higher in comparison to tracheae which were not pretreated with ROS scavengers (**p<0.01; A & C). (B & D) The inhibiting effect by Zym (0.1 mg/ml) onto Epi (10⁻⁸ M) evoked PTV-increase was also reduced by the simultaneous application of the ROS scavengers ACC and Tempol (**p<0.01; B & D). (E) Application of ROS scavengers ACC (20 mM) alone or in combination with Tempol (5 mM) did not change PTV. Mann Whitney U-test. Mean ± S.E.M.. (control: n = 7; all other experiments n = 5, n: tracheae from n animals).