Mice hypomorphic for Pitx3 show robust entrainment of circadian behavioral and metabolic rhythms to scheduled feeding.

ABSTRACT: Pitx3^ak mice lack a functioning retina and develop fewer than 10% of dopamine neurons in the substantia nigra. Del Río-Martín et al. (2019) reported that entrainment of circadian rhythms to daily light-dark (LD) cycles is absent in these mice, and that rhythms of locomotor activity, energy expenditure, and other metabolic variables are disrupted with food available ad libitum and fail to entrain to a daily feeding. The authors propose that retinal innervation of the suprachiasmatic nucleus is required for development of cyclic metabolic homeostasis, but methodological issues limit interpretation of the results. Using standardized feeding schedules and procedures for distinguishing free-running from entrained circadian rhythms, we confirm that behavioral and metabolic rhythms in

SUBMITTER: Scarpa LL 

PROVIDER: S-EPMC8788647 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature