Fig. 6.

Increased OPN expression associates with left ventricular dysfunction and increased myocyte apoptosis. Doxycycline (DOX) was removed from the diet when the mice were 4 mo old. A: M-mode echocardiographic images obtained from sham (0 wk) and dual transgenic (MHC-OPN) mice 4 wk after DOX withdrawal (Doxy off). Percent fractional shortening (%FS) was measured using echocardiography at 0, 2, 4, and 8 wk after DOX withdrawal (B). *P < 0.05 vs. 0 wk MHC-OPN; $P < 0.05 vs. 4 wk MHC-OPN; n = 4–10. C: quantitative analysis of myocyte apoptosis using TUNEL assay. *P < 0.05 vs. sham; n = 4.