Fig. 1.

NECA-dependent upregulation of VEGF production is associated with an increase in VEGF transcription, AP-1 activity, and JunB accumulation in various human and mouse cell types. HMEC-1 cells (A, E, I, M), HMC-1 cells (B, F, J, N), mCSC cells (C, G, K, O), and LLC cells (D, H, L, P) were either not transfected (A–D, M–P) or transfected with plasmids encoding VEGF (E–H) or AP-1 (I–L) luciferase reporters and were incubated in the absence (Basal) or presence of 10 μM NECA for 6 (A–L) or 3 (M–P) hours. VEGF release (A–D), VEGF (E–H), and AP-1 (I–L) reporter activities and JunB protein levels (M–P) were analyzed as described in Materials and Methods. Values are presented as mean ± S.E.M. (n = 3–10) in A–L. Asterisks indicate the statistical difference (*P < 0.05; **P < 0.01; ***P < 0.001) compared with basal values by two-tailed unpaired t tests. Representative blots of 3–5 experiments are shown in M–P.