title: Time course for synchronization of spontaneous locomotor activity in the rat following reversal of the daylight (12:12 h) cycle.
abstract: The present results demonstrate that 5-7 days on a reversed light-dark cycle (12:12 h) is sufficient for the synchronization of spontaneous locomotor activity with the new circadian rhythm in rats. Once established, the circadian rhythm is stable for at least 3 days under constant illumination conditions. Reversal of the light-dark cycle appears to be both a reliable and practical procedure in everyday laboratory work.
authors.affiliation: Department of Behavioural Pharmacology, Astra Arcus AB, Södertälje, Sweden.
authors.forename: V
authors.initials: V
authors.lastname: Hillegaart
authors.forename: S
authors.initials: S
authors.lastname: Ahlenius
mesh_terms: D000818:Animals; D002940:Circadian Rhythm; D008027:Light; D008297:Male; D009043:Motor Activity; D051381:Rats; D017207:Rats, Sprague-Dawley; D012016:Reference Values; D012894:Sleep Stages