GABA and Gi/o differentially control circadian rhythms and synchrony in clock neurons.

ABSTRACT: Neurons in the mammalian suprachiasmatic nuclei (SCN) generate daily rhythms in physiology and behavior, but it is unclear how they maintain and synchronize these rhythms in vivo. We hypothesized that parallel signaling pathways in the SCN are required to synchronize rhythms in these neurons for coherent output. We recorded firing and clock-gene expression patterns while blocking candidate signaling pathways for at least 8 days. GABA(A) and GABA(B) antagonism increased circadian peak firing rates and rhythm precision of cultured SCN neurons, but G(i/o) did not impair synchrony or rhythmicity. In contrast, inhibiting G(i/o) with pertussis toxin abolished rhythms in most neurons and desynchronized the population, phenocopying the loss of vasoactive intestinal polypeptide (VIP). Daily VIP rec

SUBMITTER: Aton SJ 

PROVIDER: S-EPMC1748197 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature