OSM induces biphasic TF mRNA expression.
(A,B) Kinetics of TF mRNA induced by OSM and PDGF-BB. SMCs were incubated with OSM (10 ng/mL) and PDGF-BB (20 ng/mL) for the indicated times, and RNA was extracted from 5 × 106 cells at the end of each incubation and analyzed as described in “Materials and methods.” The blots were rehybridized with G3PDH to demonstrate equal RNA loading. Solid columns represent the aggregate of densitometry analysis from 4 separate experiments. *P < .05 compared to 0 hour. (C) SMCs cultures were prestimulated with OSM for 30 minutes, washed 3 times, and incubated in serum-free DME/F12 medium for the indicated times. RNA was extracted at the end of each incubation and analyzed for TF mRNA expression by Northern blotting. (D) OSM-conditioned medium from 24-hour SMC cultures were used to stimulate SMCs for a further 24 hours in the presence or absence of a neutralizing monoclonal antibody to OSM. After 24 hours, RNA was extracted and analyzed for TF expression by Northern blotting. Results are representative of 3 separate experiments.
