Table 1.

Echocardiographic and necropsy analyses of young (3–6 mo old) and old (16–21 mo old) wild-type (WT) and macrophage matrix metalloproteinase-9 (MMP-9) transgenic (TG) mice

Young WTOld WTYoung TGOld TG
n (Male)11 (6)15 (10)20 (10)20 (10)
Age, mo3.7 ± 0.118.3 ± 0.64.7 ± 0.218.9 ± 0.4
Body weight, g26.5 ± 1.029.8 ± 1.0*24.7 ± 0.932.8 ± 1.3*
End systolic dimension, mm2.1 ± 0.22.2 ± 0.11.9 ± 0.12.1 ± 0.1
End diastolic dimension, mm3.4 ± 0.13.6 ± 0.13.2 ± 0.13.6 ± 0.1*
Fractional shortening, %41 ± 339 ± 342 ± 242 ± 2
Interventricular septal wall thickness, diastole, mm0.62 ± 0.020.74 ± 0.03*0.69 ± 0.020.86 ± 0.03*
Posterior wall thickness, diastole, mm0.61 ± 0.040.65 ± 0.030.64 ± 0.020.71 ± 0.03
Mean wall thickness, diastole, mm0.61 ± 0.020.70 ± 0.02*0.66 ± 0.020.79 ± 0.02*
Left ventricular mass, mg87.6 ± 3.788.2 ± 3.880.0 ± 2.788.7 ± 2.9*
Left ventricular mass/tibia length5.1 ± 0.25.0 ± 0.24.7 ± 0.15.0 ± 0.2
Right ventricular mass, mg21.6 ± 1.721.8 ± 1.722.7 ± 1.026.5 ± 1.0*
Right ventricular mass/tibia length1.3 ± 0.11.3 ± 0.11.3 ± 0.11.5 ± 0.1*
  • Data are expressed as means ± SE. Mean wall thickness, average of the left ventricle interventricular septum wall thickness and posterior wall thickness. WT, wild-type; MMP-9, macrophage matrix metalloproteinase-9; TG, transgenic mice.

  • * P < 0.05 vs. respective young.

  • P < 0.05 vs. age-matched WT.