Table 1.
Changes in light–dark ratios in rats with lateral hypothalamic injections of saline or Hcrt2-SAP
| Group | 6 d after injection | 14 d after injection | ||||||
|---|---|---|---|---|---|---|---|---|
| Wake | SWS | REM | EEG δ power in SWS | Wake | SWS | REM | EEG δ power in SWS | |
| Hcrt cell loss >60% (n = 9) | 1.00 ± 0.12* | 1.25 ± 0.15* | 0.46 ± 0.09* | 1.12 ± 0.08* | 0.90 ± 0.10* | 1.39 ± 0.17* | 0.45 ± 0.05* | 1.21 ± 0.07* |
| Hcrt cell loss <30% (n = 3) | 0.38 ± 0.09 | 3.56 ± 1.00 | 2.63 ± 1.30 | 1.63 ± 0.16 | 0.33 ± 0.04 | 3.73 ± 0.69 | 3.77 ± 0.65 | 1.54 ± 0.27 |
| Saline (n = 8) | 0.43 ± 0.03 | 2.99 ± 0.28 | 3.15 ± 0.61 | 1.68 ± 0.17 | 0.36 ± 0.03 | 3.28 ± 0.37 | 4.41 ± 0.76 | 1.80 ± 0.21 |
Values (±SEM) represent ratio of wakefulness, SWS, or REM sleep percentage during light-on period versus its corresponding value during light-off period. For EEG δ power, the values represent the ratio of δ power during the 2 hr period after lights on (7 A.M. to 9 A.M.) versus the 2 hr period after lights off (7 P.M. to 9 P.M.). For δ power, the 2 hr time points represented the peak and nadir of the δ power across the 24 hr in saline-treated rats, a finding that is consistent with the waxing and waning of EEG δ power (Borbely, 1994).
*
p < 0.05, significant difference compared with the values of the saline group.