Send to

Choose Destination
Nat Neurosci. 2006 Aug;9(8):1041-9. Epub 2006 Jul 16.

BK calcium-activated potassium channels regulate circadian behavioral rhythms and pacemaker output.

Author information

Department of Molecular and Cellular Physiology and Howard Hughes Medical Institute, Stanford University, Stanford, California 94305, USA.

Erratum in

  • Nat Neurosci. 2006 Sep;9(9):1193.


Spontaneous action potentials in the suprachiasmatic nucleus (SCN) are necessary for normal circadian timing of behavior in mammals. The SCN exhibits a daily oscillation in spontaneous firing rate (SFR), but the ionic conductances controlling SFR and the relationship of SFR to subsequent circadian behavioral rhythms are not understood. We show that daily expression of the large conductance Ca(2+)-activated K(+) channel (BK) in the SCN is controlled by the intrinsic circadian clock. BK channel-null mice (Kcnma1(-/-)) have increased SFRs in SCN neurons selectively at night and weak circadian amplitudes in multiple behaviors timed by the SCN. Kcnma1(-/-) mice show normal expression of clock genes such as Arntl (Bmal1), indicating a role for BK channels in SCN pacemaker output, rather than in intrinsic time-keeping. Our findings implicate BK channels as important regulators of the SFR and suggest that the SCN pacemaker governs the expression of circadian behavioral rhythms through SFR modulation.

Comment in

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center