Bridging the gap: coupling single-cell oscillators in the suprachiasmatic nucleus. Nat Neurosci 8:10-12

Nature Neuroscience (Impact Factor: 16.1). 02/2005; 8(1):10-2. DOI: 10.1038/nn0105-10
Source: PubMed


Neurons in the mammalian master clock can maintain circadian rhythms in isolation, but must synchronize to function as a time-keeping system. A new study finds that gap junctions between neurons promote synchronous electrical activity and rhythmic behavior.

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Available from: Christopher S Colwell, Dec 12, 2013
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    • "In addition, nNOS knockout mice (which appear to be normally entrained to light) exhibit only moderate decreases in light-induced cFOS expression [22]. SCN neurons are single cell autonomous oscillators [23] capable of generating coherent circadian output [8] [9] [24] Among other mechanisms, neuropeptide signaling [25], Na + channelsmediated action potentials, gap junction-mediated processes [26] [27] [28] and GABAergic neurotransmission [29] [30] have been proposed to mediate cellular coupling in the SCN [27]. Two subdivisions are defined within the SCN: the VL region is located above the optic chiasm and is characterized by neurons that synthesize vasoactive intestinal polypeptide (VIP) and GRP, surrounded by the DM region which contains arginine–vasopressin and calretinin neurons [31] [32] [33]. "
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