Motor activity correlates negatively with free-running period, while positively with serotonin contents in SCN in free-running rats.
Free-running period of blinded rats kept in a cage with a running wheel varied markedly, while it varied little in rats kept in a cage without a running wheel. The mean free-running period of the former group is significantly shorter than that of the latter. In the former, the free-running period correlated negatively with motor activity, indicating that activity affects the free-running period. In both groups, essentially similar diurnal patterns of biogenic amines and their metabolites were observed in various discrete areas in the brain examined. However, there was a significant difference between the two groups in several areas. In the SCN, 5-HT content correlated positively with motor activity, consequently correlated negatively to the free-running period at 3 out of 4 sampling times over 24 h but no such correlation was observed in other monoamines and their metabolites examined. These facts suggest that 5-HT may be associated with modification of the free-running period.
Shioiri
T
T
Department of Psychiatry, Shiga University of Medical Sciences, Japan.
Takahashi
K
K
Yamada
N
N
Takahashi
S
S
D000818:Animals; D001931:Brain Mapping; D002940:Circadian Rhythm / Q000502:physiology*; D003342:Corpus Striatum / Q000502:physiology; D004298:Dopamine / Q000502:physiology; D005260:Female; D005625:Frontal Lobe / Q000502:physiology; D006624:Hippocampus / Q000502:physiology; D007031:Hypothalamus / Q000502:physiology; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D009638:Norepinephrine / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D012683:Sensory Deprivation / Q000502:physiology; D012701:Serotonin / Q000502:physiology*; D012931:Social Environment; D013493:Suprachiasmatic Nucleus / Q000502:physiology*
D012701:Serotonin; D004298:Dopamine; D009638:Norepinephrine