Table 1. Comparison of Cardiovascular Fitness in Aged LCR vs. HCR Rats.
| Characteristic | LCR | HCR | p value | |
|---|---|---|---|---|
| Age, days | Days | 488.4 (0.7) | 487.9 (1.1) | 0.13 |
| Body weight | N | 15 | 16 | |
| Week 1, g | 347.4 (57.7) | 236.5 (23.1) | <0.001 | |
| Week 8, g | 350.4 (54.25) | 242.4 (24.46) | <0.001 | |
| Gain, g | 2.95 (11.13) | 5.89 (8.73) | 0.42 | |
| NMR Body Composition | N | 15 | 16 | |
| Body weight, g | 349.1 (58.72) | 239.5 (21.77) | <0.001 | |
| Fat,% | 23.3 (9.38) | 8.8 (2.83) | <0.001 | |
| Lean, % | 66.0 (7.32) | 78.7 (2.12) | <0.001 | |
| Fluid, % | 7.4 (0.62) | 7.5 (0.21) | 0.45 | |
| Home-Cage Activitya | N | 14 | 16 | |
| Dark cycle | Total Movement, ct/kg/min | 19.9 (13.4) | 33.0 (15.9) | 0.11 |
| Light cycle | Total Movement, ct/kg/min | 7.3 (3.1) | 8.5 (3.7) | 0.51 |
| 24-hour | Total Movement, ct/kg/min | 13.8 (7.7) | 21.1 (9.6) | 0.13 |
| CLAMS Activity | N | 14 | 14 | |
| Dark cycle | X-Horizontal Movement,ct/hr | 222.5 (68.7) | 316.0 (73.4) | 0.002 |
| Z-Vertical Movement, ct/hr | 413.9 (128.0) | 574.1 (130.5) | <0.003 | |
| Total Movement, ct/hr | 631.2 (121.4) | 858.7 (109.9) | <0.001 | |
| Light cycle | X-Horizontal Movement,ct/hr | 77.4 (15.9) | 117.5 (24.9) | <0.001 |
| Z-Vertical Movement, ct/hr | 127.2 (43.7) | 180.9 (57.8) | 0.010 | |
| Total Movement, ct/hr | 257.9 (46.2) | 368.7 (73.8) | <0.001 | |
| 24-hour | X-Horizontal Movement,ct/hr | 152.2 (41.8) | 220.2 (41.6) | <0.001 |
| Z-Vertical Movement,ct/hr | 275.1 (84.16) | 384.9 (21.5) | 0.001 | |
| Total Movement,ct/hr | 451.4 (78.8) | 622.8 (66.9) | <0.001 | |
| CLAMS Metabolic | N | 14 | 14 | |
| Dark cycle | VO2,,ml/kg/hr | 1310.4 (222.9) | 1634.5 (485.4) | 0.03 |
| VO2 0.75BW.,ml/kg0.75BW | 5608.0 (773.6) | 6872.8 (731.7) | <0.001 | |
| VO2 lean ,ml/kglean | 1966.2 (221.1) | 2199.4 (206.1) | 0.008 | |
| VCO2,ml/kg/hr | 1287.7 (247.6) | 1688.9 (184.4) | <0.001 | |
| RQ | 0.98 (0.04) | 0.97 (0.02) | 0.15 | |
| Light cycle | VO2,,ml/kg/hr | 1080.8 (181.6) | 1365.1 (403.9) | 0.024 |
| VO2 0.75BW,,ml/kg0.75BW | 4614.2 (644.1) | 5749.4 (561.9) | <0.001 | |
| VO2 lean ,ml/kglean | 1618.6 (204.7) | 1840.6 (170.1) | 0.004 | |
| VCO2,ml/kg/hr | 1033.3 (204.3) | 1385.4 (155.2) | <0.001 | |
| RQ | 0.96 (0.05) | 0.95 (0.03) | 0.53 | |
| 24-hour | VO2,,ml/kg/hr | 1199.9 (200.4) | 1505.4 (445.5) | 0.027 |
| VO2 0.75BW,,ml/kg0.75BW | 5130.5 (696.4) | 6335.7 (561.9) | <0.001 | |
| VO2 lean ,ml/kglean | 1799.0 (207.1) | 2027.4 (172.7) | 0.005 | |
| VCO2,ml/kg/hr | 1166.2 (224.5) | 1544.0 (166.5) | <0.001 | |
| RQ | 0.97 (0.04) | 0.96 (0.03) | 0.28 | |
| Blood Sugar | N | 15 | 16 | |
| Random Glucose,mg/dL | 106.9 (8.4) | 91.5 (6.5) | <0.001 |
a
Rats housed 2 per cage. Abbreviations: g, grams; ct/kg/min, counts per kilogram per minute; ct/hr, counts per hour.