@entity750 ( @entity750 ) is an important regulator of the @entity1 circadian system, and has been implicated in modulating entrained and free-running rhythms, as well as photic and non-photic phase shifting. In general, @entity750 appears to oppose the actions of light on the circadian system of nocturnal rodents. As well, @entity750 mediates, at least in part, some non-photic responses. The 5-HT1A, 1B and 7 receptors regulate these acute responses to zeitgebers. @entity750 also regulates some entrained and free-running properties of the circadian clock. The receptors that contribute to these phenomena have not been fully examined. Here, we use @entity19472 knockout (KO) @entity19 to examine the response of the @entity19 circadian system to a variety of lighting conditions, including a normal light-dark cycle (LD), T-cycles, phase advanced LD cycles, constant darkness ( @entity336 ), constant light (LL) and a 6hour dark pulse starting at CT5. Relative to wildtype @entity19 , the @entity19472 KO @entity19 have lower levels of activity during the first 8h of the night/subjective night in LD and LL, later activity onsets on transient days during re-entrainment, shorter free-running periods in LL when housed with wheels, and smaller phase shifts to dark pulses. No differences were noted in activity levels during @entity336 , alpha under any light condition, free-running period in @entity336 , or phase angle of entrainment in LD. While the @entity19472 plays an important role in regulating photic and non-photic phase shifting, its contribution to entrained and free-running properties of the circadian clock is relatively minor.

Effects of lighting condition on circadian behavior in @entity19472 knockout XXXX .

@entity1 :: ('9606', 'Species') :: ['mammalian'] @entity336 :: ('MESH:C536170', 'Disease') :: ['DD'] @entity19 :: ('10090', 'Species') :: ['mice', 'mouse'] @entity750 :: ('MESH:D012701', 'Chemical') :: ['Serotonin', '5-HT'] @entity19472 :: ('15550(Tax:10090)', 'Gene') :: ['5-HT1A receptor']
@entity19 :: (10090,Species) :: ['mice']
