Analysis of TF mRNA and enzymatic activity in mouse aortas. RNA was harvested from the aortic media of TF^flox/flox mice (Flox/flox; n = 3) and VSMC-specific TF-deficient mice (Flox/flox/Cre; n = 5) and analyzed for TF mRNA by (A) RT-PCR and (B) real time RT-PCR. For real time RT-PCR, TF mRNA levels in Flox/flox/Cre mice are expressed relative to those of Flox/flox mice, defined arbitrarily as 1.0. (C) TF activity was measured in extracts of aortic media of Flox/floxCre (n = 6) and Flox/flox (n = 4) mice by 2-stage colorimetric Xa generation assay and is expressed as pM factor Xa/min. *P < .05.