Figure 1
Representative actograms of Rw, Tb and serum melatonin profile. A, B, C: a synchronized animal (rat # 1 in Table 1); D, E. F: an animal with a damped melatonin rhythm (rat # 5 in Table 1); G, H, I: a desynchronized animal (rat # 21 in Table 1). Plots D and E show only the last 40 days of the experiment.
Table 1
Circadian parameters for Rw and Tb(mean ± SEM) and serum melatonin for each animal tested. Animals in which the circadian rhythm of serum melatonin was desynchronized from Rw and Tb, are indicated in bold. Animals in which the serum melatonin rhythm was damped are indicated in italic. (Amp. = amplitude)
| Running Wheel | Body Temperature | Melatonin | ||||||
| Mesor | Amp. | τ | Mesor | Amp. | τ | Range | Peak | |
| Rat # 1 | 0.6 ± 0.2 | 19.3 ± 3.1 | 25.4 | 37.2 ± 0.1 | 2.1 ± 0.2 | 25.4 | 26–559. | 16 |
| Rat # 2 | 0.7 ± 0.1 | 19.3 ± 3.1 | 25.1 | 36.8 ± 0.1 | 1.8 ± 0.2 | 25.0 | 12–122 | 4 |
| Rat # 3 | 0.1 ± 0.1 | 5.6 ± 1.2 | 24.6 | 37.0 ± 0.1 | 1.9 ± 0.2 | 24.6 | 10–146 | 4 |
| Rat # 4 | NS | NS | 12–544 | NA | ||||
| Rat # 5 | 6.6 ± 1.9 | 45.6 ± 2.1 | 25.1 | 37.6 ± 0.1 | 2.8 ± 0.2 | 25.2 | 105–204 | 16 |
| Rat # 6 | 2.6 ± 0.7 | 39.7 ± 5.0 | 24.3 | 37.5 ± 0.2 | 1.9 ± 0.2 | 24.3 | 38–306 | 16 |
| Rat # 7 | 3.4 ± 1.1 | 30.8 ± 3.1 | 24.4 | 36.9 ± 0.2 | 1.7 ± 0.1 | 24.4 | 109–204 | 20 |
| Rat # 8 | 0.4 ± 0.1 | 8.3 ± 3.4 | 25.0 | 38.5 ± 0.1 | 2.1 ± 0.4 | 25.1 | 32–206 | 20 |
| Rat # 9 | 3.3 ± 0.8 | 48.8 ± 7.7 | 25.3 | 37.3 ± 0.1 | 2.3 ± 0.2 | 25.2 | 138–188 | 20 |
| Rat # 10 | 0.5 ± 0.1 | 12.2 ± 2.0 | 24.3 | 36.8 ± 0.1 | 1.8 ± 0.1 | 24.4 | 108–358 | 4 |
| Rat # 11 | 6.0 ± 1.3 | 53.5 ± 5.2 | 25.1 | 37.6 ± 0.2 | 2.4 ± 0.4 | 25.1 | 128–572 | 0 |
| Rat # 12 | 1.3 ± 0.2 | 23.5 ± 6.1 | 25.2 | 37.4 ± 0.1 | 1.8 ± 0.2 | 25.2 | 158–354 | 16 |
| Rat # 13 | 0.4 ± 0.1 | 8.9 ± 1.1 | 25.1 | 37.1 ± 0.1 | 1.6 ± 0.2 | 25.1 | 97–707 | 20 |
| Rat # 14 | 0.7 ± 0.1 | 15.6 ± 1.3 | 25.2 | 37.3 ± 0.1 | 2.1 ± 0.2 | 25.1 | 144–238 | 20 |
| Rat # 15 | 0.9 ± 0.2 | 15.1 ± 1.4 | 24.6 | 37.5 ± 0.1 | 2.1 ± 0.2 | 24.5 | 118–566 | 8 |
| Rat # 16 | 1.2 ± 0.3 | 24.7 ± 4.0 | 25.1 | 37.6 ± 0.1 | 2.3 ± 0.6 | 25.2 | 155–278 | 16 |
| Rat # 17 | 0.6 ± 0.1 | 14.8 ± 3.1 | 24.3 | 37.2 ± 0.1 | 1.5 ± 0.3 | 24.2 | 26–113 | 8 |
| Rat # 18 | 1.1 ± 0.6 | 15.9 ± 2.8 | 25.0 | 37.4 ± 0.1 | 2.0 ± 0.5 | 25.0 | 20–423 | 16 |
| Rat # 19 | 0.7 ± 0.1 | 15.8 ± 2.5 | 24.5 | 37.7 ± 0.1 | 2.0 ± 0.2 | 24.4 | 20–104 | 16 |
| Rat # 20 | 1.0 ± 0.2 | 16.1 ± 1.3 | 24.5 | 37.6 ± 0.1 | 1.9 ± 0.4 | 24.5 | 21–120 | 16 |
| Rat # 21 | 1.1 ± 0.1 | 20.7 ± 1.9 | 25.4 | 37.4 ± 0.1 | 2.1 ± 0.2 | 25.4 | 27–295 | 4 |
| Rat # 22 | 0.7 ± 0.1 | 13.7 ± 1.5 | 25.1 | 37.4 ± 0.1 | 1.9 ± 0.2 | 25.1 | 34–559 | 20 |
Table 2
Circadian parameters for Rw and Tb (mean ± SEM). Group 1 = synchronized animals in which serum melatonin showed a high (more than 5) night-to-day ratio. Group 2 = synchronized animals in which serum melatonin showed a night-to-day ratio smaller than 2. Group 3 = desynchronized animals (i.e., animals in which the serum melatonin levels peaked during the subjective day). No significant differences were observed among the groups in any of the circadian parameters investigated (ANOVA, P > 0.1).
| Running wheel activity | Body Temperature | ||||||
| N | Mesor | Amplitude | τ | Mesor | Amplitude | τ | |
| Group 1 | 8 | 0.9 ± 0.2 | 17.2 ± 3.4 | 24.9 ± 0.1 | 37.5 ± 0.1 | 1.9 ± 0.1 | 24.9 ± 0.1 |
| Group 2 | 6 | 2.7 ± 0.9 | 31.5 ± 5.4 | 25.0 ± 0.1 | 37.3 ± 0.1 | 2.2 ± 0.2 | 25.0 ± 0.1 |
| Group 3 | 7 | 1.4 ± 0.8 | 20.2 ± 5.9 | 24.8 ± 0.2 | 37.2 ± 0.1 | 1.9 ± 0.1 | 24.7 ± 0.2 |