| First Author | Solarewicz JZ | Year | 2015 |
| Journal | Am J Physiol Regul Integr Comp Physiol | Volume | 308 |
| Issue | 1 | Pages | R10-7 |
| PubMed ID | 25394829 | Mgi Jnum | J:223880 |
| Mgi Id | MGI:5660572 | Doi | 10.1152/ajpregu.00400.2014 |
| Citation | Solarewicz JZ, et al. (2015) The sleep-wake cycle and motor activity, but not temperature, are disrupted over the light-dark cycle in mice genetically depleted of serotonin. Am J Physiol Regul Integr Comp Physiol 308(1):R10-7 |
| abstractText | We examined the role that serotonin has in the modulation of sleep and wakefulness across a 12-h:12-h light-dark cycle and determined whether temperature and motor activity are directly responsible for potential disruptions to arousal state. Telemetry transmitters were implanted in 24 wild-type mice (Tph2(+/+)) and 24 mice with a null mutation for tryptophan hydroxylase 2 (Tph2(-/-)). After surgery, electroencephalography, core body temperature, and motor activity were recorded for 24 h. Temperature for a given arousal state (quiet and active wake, non-rapid eye movement, and paradoxical sleep) was similar in the Tph2(+/+) and Tph2(-/-) mice across the light-dark cycle. The percentage of time spent in active wakefulness, along with motor activity, was decreased in the Tph2(+/+) compared with the Tph2(-/-) mice at the start and end of the dark cycle. This difference persisted into the light cycle. In contrast, the time spent in a given arousal state was similar at the remaining time points. Despite this similarity, periods of non-rapid-eye-movement sleep and wakefulness were less consolidated in the Tph2(+/+) compared with the Tph2(-/-) mice throughout the light-dark cycle. We conclude that the depletion of serotonin does not disrupt the diurnal variation in the sleep-wake cycle, motor activity, and temperature. However, serotonin may suppress photic and nonphotic inputs that manifest at light-dark transitions and serve to shorten the ultraradian duration of wakefulness and non-rapid-eye-movement sleep. Finally, alterations in the sleep-wake cycle following depletion of serotonin are unrelated to disruptions in the modulation of temperature. |
