Circadian rhythm of the rat suprachiasmatic brain slice is rapidly reset by daytime application of cAMP analogs.
Cellular mechanisms underlying the primary circadian pacemaker in mammals were investigated by isolating rat suprachiasmatic nuclei in brain slices and maintaining them in vitro for up to 3 days. The circadian rhythm of neuronal firing rate was used to assess the phase of the pacemaker. This rhythm was rapidly reset by bath application of cAMP analogs. Moreover, the pacemaker demonstrated circadian sensitivity to analog treatment: the rhythm was advanced by application during the donor's day, but not during the donor's night. These results suggest that cAMP-mediated events may stimulate pacemaker afferents within the SCN or may directly influence the pacemaker mechanism.
Gillette
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MU
Neural and Behavioral Biology Program, University of Illinois at Urbana-Champaign 61801.
Prosser
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RA
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002940:Circadian Rhythm / Q000187:drug effects*; D000242:Cyclic AMP / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000502:physiology; D066298:In Vitro Techniques; D051381:Rats; D013493:Suprachiasmatic Nucleus / Q000187:drug effects / Q000502:physiology*; D013873:Thionucleotides / Q000494:pharmacology* / Q000502:physiology
D013873:Thionucleotides; C040017:8-benzylamino-cyclic AMP; C015929:8-((4-chlorophenyl)thio)cyclic-3',5'-AMP; D000242:Cyclic AMP