MMP3 and myocardial infarction: Significant increases in Col1a1 (1.7-fold increase; P < 0.05), Col3a1 (3.2-fold; P < 0.001), Mmp3 (2.5-fold; P < 0.01), and Tnc (2.1-fold; P < 0.01) mRNA levels were observed in control hearts after MI compared with sham hearts (Figure 5C).