Figure 4.

Adenovirus-mediated TR3 overexpression inhibits stretch-induced DNA synthesis. A: [³H]Thymidine incorporation is increased after 24 hours of cyclic stretch in mock virus-infected SMCs compared with infected, unstretched control cells. Adenovirus-mediated overexpression of TR3 completely blocked stretch-induced DNA synthesis (data from experiments in SV-SMCs derived from four independent donors). B: The expression of TR3 protein after infection of stretched, venous SMCs with TR3-encoding adenovirus as demonstrated by Western blotting (a typical example is shown after 24 hours of stretch). In stretched, TR3-infected cells, SM α-actin, calponin, and 27^Kip1 protein levels are higher than in mock-infected cells. α-Tubulin served as control for equal loading (not shown), and intensity of protein bands, corrected for the amount of α-tubulin protein, is given in arbitrary units (AU). *P < 0.01; ns, not statistically significant.