Fig. 4. Specificity of AP-1 binding to the tissue factor AP-1 regulatory element in rat lung nuclear extract (NE) from sham-operated control (C) rats and rats 2 h after they were subjected to Noble-Collip drum trauma (T). Binding reactions were carried out with AP-1 (D + P) probe containing distal (D) and proximal (P) AP-1 sites. Nuclear extracts were incubated during the following conditions from left to right: labeled SP-1 probe, in which binding was not changed in trauma; labeled AP-1 probe, which showed an increase in its binding post-trauma compared with sham-operated controls; unlabeled AP-1 probe in 100-fold excess plus labeled AP-1 probe, in which binding was inhibited by competition; and control lane with no nuclear extract (−NE).