title: Circadian rhythm in the function of central 5-HT1A receptors is endogenous in nature.
abstract: In a recent study, we found a circadian rhythm in the response of central serotonin (5-HT)1A receptors to 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT). In the present study, the 8-OH-DPAT-induced 5-HT behavioural syndrome was examined in rats kept under continuous dark (DD) conditions for 6 days. The results revealed a circadian rhythm in the behavioural response to 8-OH-DPAT under DD conditions. The pattern of this rhythm was similar to that observed under the light-dark conditions, except for the phase delay that corresponds to the period of free-running rhythm. These results strongly suggest that the rhythm in the function of central 5-HT1A receptors is driven by the endogenous oscillator.
authors.affiliation: Department of Neuropsychiatry, Oita Medical University Hasama-machi, Japan.
authors.forename: J Q
authors.initials: JQ
authors.lastname: Lu
authors.forename: H
authors.initials: H
authors.lastname: Nagayama
mesh_terms: D000818:Animals; D001921:Brain / Q000502:physiology*; D002940:Circadian Rhythm; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D011985:Receptors, Serotonin / Q000502:physiology*
chemical_list: D011985:Receptors, Serotonin