Neuropeptide Y-induced phase shifts of PER2::LUC rhythms are mediated by long-term suppression of neuronal excitability in a phase-specific manner.

ABSTRACT: Endogenous circadian rhythms are entrained to the 24-h light/dark cycle by both light and nonphotic stimuli. During the day, nonphotic stimuli, such as novel wheel-induced exercise, produce large phase advances. Neuropeptide Y (NPY) release from the thalamus onto suprachiasmatic nucleus (SCN) neurons at least partially mediates this nonphotic signal. The authors examined the hypothesis that NPY-induced phase advances are accompanied by suppression of PER2 and are mediated by long-term depression of neuronal excitability in a phase-specific manner. First, it was found that NPY-induced phase advances in PER2::LUC SCN cultures are largest when NPY (2.35 µM) is given in the early part of the day (circadian time [CT] 0-6). In addition, PER2::LUC levels in NPY-treated (compared to vehicle-treate

SUBMITTER: Besing RC 

PROVIDER: S-EPMC3568491 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature