Fig. 7.
Involvement of VSMC ECM in the functional binding of tPA. The ECM remaining after removal of VSMCs by lysis was preincubated with tPA and assayed for plasmin generation as in Fig 5. In the experiment shown, the tPA binding constants in the presence of cells were determined to be kd1 = 16 nmol/L (175 [pmol/L]⋅min−1) and kd2 = 1,000 nmol/L (500 [pmol/L]⋅min−1) and in the absence of cells a single class of site kd = 590 nmol/L (305 [pmol/L]⋅min−1).