Influence of short-term constant light on phase shift of mouse circadian locomotor activity rhythm induced by agonist and antagonist of serotonin

摘要

Despite the large body evidence from a variety of studies, the role of the serotonergic projection in the circadian system is still unclear. Previous work suggested that 5-HT is involved in both the response of SCN neurons to light and the phase-resetting properties of nonphotic stimuli. In hamsters, short exposure to constant light potentiates circadian phase-shifting caused by nonphotic stimuli, and the 5-HT pathway may be connected with this effect. The aim of this study was to determine whether a similar effect obtains in mice. We examined brief light-potentiation of (R)-(+)-8-OH-DPAT (8-hydroxyl-2-[di-n-propyloamino]-tetralin) and WAY100635 phase resetting, and found that short constant light before administration of (R)-(+)-8-OH-DPAT significantly enhanced the delays of the phase shift of the locomotor activity rhythm as compared with NaCl-injected animals. The transition from short LL to DD caused a phase shift, and WAY100635 attenuated this effect.View full textDownload full textKeywordsserotonin, (R)-(+)-8-OH-DPAT, WAY100635, locomotor activity rhythm, constant lightRelated var addthis_config = { ui_cobrand: "Taylor & Francis Online", services_compact: "citeulike,netvibes,twitter,technorati,delicious,linkedin,facebook,stumbleupon,digg,google,more", pubid: "ra-4dff56cd6bb1830b" }; Add to shortlist Link Permalink http://dx.doi.org/10.1080/09291010903018016