Table 1.
Body weight and echocardiographic characteristics of female F344 rats
| 6 Mo (n = 7) | 18 Mo (n = 9) | 22 Mo (n = 8) | P Value (One-Way ANOVA) | |
|---|---|---|---|---|
| Body weight, g | 203.4 ± 8.7 | 307.1 ± 7.7* | 327.6 ± 8.7* | <0.0001 |
| HR, beats/min | 326.4 ± 12.6 | 321.4 ± 11.1 | 294.9 ± 12.6 | 0.185 |
| FS, % | 52.2 ± 3.1 | 51.4 ± 2.8 | 47.2 ± 2.9 | 0.453 |
| IVSd, mm | 1.8 ± 0.1 | 1.7 ± 0.1 | 1.8 ± 0.1 | 0.553 |
| IVSs, mm | 2.8 ± 0.2 | 3.0 ± 0.1 | 2.9 ± 0.1 | 0.592 |
| LVIDd, mm | 5.3 ± 0.2 | 6.7 ± 0.2* | 6.6 ± 0.2* | <0.0001 |
| LVIDs, mm | 2.5 ± 0.2 | 3.2 ± 0.2 | 3.5 ± 0.2* | 0.025 |
| LVPWd, mm | 1.8 ± 0.1 | 1.9 ± 0.1 | 1.8 ± 0.1 | 0.775 |
| LVPWs, mm | 2.7 ± 0.2 | 3.0 ± 0.1 | 2.7 ± 0.1 | 0.282 |
| dBA, mm | 4.6 ± 0.4 | 4.5 ± 0.3 | 5.1 ± 0.3 | 0.473 |
| E/E' | 29.0 ± 6.3 | 41.4 ± 6.3 | 37.3 ± 6.8 | 0.379 |
Values are means ± SE. HR, heart rate; FS, fractional shortening; IVSd, diastolic thickness of the septum; IVSs, systolic thickness of the septum; LVIDd, diastolic left ventricular inner diameter; LVIDs, systolic left ventricular inner diameter; LVPWd, diastolic thickness of the left ventricular posterior wall; LVPWs, systolic thickness of the left ventricular posterior wall; dBA, normal distance between the imaging planes; E/E′,ratio of peak early mitral valve flow to peak early mitral valve septal annulus velocity.
*
Signficant difference vs. 6-mo values (Tukey's honestly significant difference; P < 0.05).