title: Impact of dispersed coupling strength on the free running periods of circadian rhythms.
abstract: The dominant endogenous clock, named the suprachiasmatic nucleus (SCN), regulates circadian rhythms of behavioral and physiological activity in mammals. One of the main characteristics of the SCN is that the animal maintains a circadian rhythm with a period close to 24 h in the absence of a daily light-dark cycle (called the free running period). The free running period varies among species due to heterogeneity of the SCN network. Previous studies have shown that the heterogeneity in cellular coupling as well as in intrinsic neuronal periods shortens the free running period. Furthermore, as derived from experiments, one neuron's coupling strength is negatively associated with its period. It is unknown what the effects of this association between coupling strength and period are on the free running period and how the heterogeneity in coupling strength influences this free running period. In the present study we found that in the presence of a negative relationship between one neuron's coupling strength and its period, surprisingly, the dispersion of coupling strengths increases the free running period. Our present finding may shed new light on the understanding of the heterogeneous SCN network and provides an alternative explanation for the diversity of free running periods between species.
authors.affiliation: Business School, University of Shanghai for Science and Technology, Shanghai 200093, P. R. China.
authors.forename: Changgui
authors.initials: C
authors.lastname: Gu
authors.affiliation: Laboratory for Neurophysiology, Department of Molecular Cell Biology, Leiden University Medical Center, 2300RC Leiden, The Netherlands.
authors.forename: Jos H T
authors.initials: JH
authors.lastname: Rohling
authors.affiliation: School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou 221116, China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Liang
authors.affiliation: Business School, University of Shanghai for Science and Technology, Shanghai 200093, P. R. China.
authors.forename: Huijie
authors.initials: H
authors.lastname: Yang
mesh_terms: D000818:Animals; D002940:Circadian Rhythm; D008959:Models, Neurological; D009474:Neurons / Q000166:cytology; D013493:Suprachiasmatic Nucleus / Q000166:cytology / Q000502:physiology*