Figure 3.

Role of L-arginine availability in impaired iNANC nerve-induced relaxation of guinea pig tracheal smooth muscle after allergen-challenge. Electrical field stimulation-induced relaxation of precontracted tracheal open-ring preparations obtained from unchallenged and from OA-challenged guinea pigs in the absence and presence of L-arginine (5.0 mM). Results are means ± s.e.m. of 4 (OA-challenged) to 7 (unchallenged) experiments. *P < 0.05 and **P < 0.01 compared to unchallenged control, ^†P < 0.05 compared to OA-challenged control.