Table 4.
Characteristics at end study
| Group |
||||
|---|---|---|---|---|
| Control | 10 Gy | 20 Gy | P Value (ANOVA) | |
| n | 12 | 10 | 10 | |
| Body wt, g | 627 ± 75 | 614 ± 63 | 584 ± 56 | 0.31 |
| Conscious heart rate, beats/min | 346 ± 35 | 314 ± 42 | 345 ± 35 | 0.10 |
| Conscious systolic BP, mmHg | 143 ± 17 | 138 ± 18 | 143 ± 17 | 0.75 |
| Hematocrit | 0.55 ± 0.04 | 0.56 ± 0.03 | 0.57 ± 0.02 | 0.34 |
| T4, μg/dl | ||||
| Plasma | 5.4 ± 0.9 | 8.0 ± 2.8* | 7.4 ± 2.1 | 0.014 |
| Plasma free | 2.4 ± 0.4 | 3.3 ± 1.3 | 3.1 ± 0.9 | 0.069 |
| LVEDV, μl | 754 ± 204 | 611 ± 83 | 640 ± 81 | 0.056 |
| Posterior wall thickness, mm | 1.87 ± 0.13 | 1.78 ± 0.24 | 1.98 ± 0.28 | 0.15 |
| Heart rate, beats/min | 324 ± 38 | 311 ± 33 | 306 ± 45 | 0.55 |
| LV systolic pressure, mmHg | 105 ± 17 | 105 ± 20 | 108 ± 20 | 0.93 |
| Arterial elastance, mmHg/ml | 174 ± 69 | 212 ± 60 | 178 ± 40 | 0.38 |
| Heart wt, mg/g | 2.57 ± 0.19 | 2.52 ± 0.36 | 2.69 ± 0.29 | 0.41 |
| Lung wt, mg/g | 3.48 ± 0.50 | 4.08 ± 0.92 | 5.38 ± 3.01 | 0.08 |
| ANP mRNA (normalized to control) | 1.00 ± 1.42 | 2.28 ± 1.36* | 3.76 ± 2.85* | N/A |
| BNP mRNA (normalized to control) | 1.00 ± 0.84 | 6.54 ± 8.88* | 6.66 ± 3.99* | N/A |
Values are means ± SD; n, number of rats. BP, blood pressure; T4, thyroxine; LVEDV, left ventricular end-diastolic volume (echo). Values for heart rate and LV systolic pressure were obtained at cardiac catheterization; N/A, not applicable.
*
P < 0.05 vs. control.