Document Detail


Forced desynchronization of activity rhythms in a model of chronic jet lag in mice.
MedLine Citation:
PMID:  22306974     Owner:  NLM     Status:  In-Data-Review    
Abstract/OtherAbstract:
We studied locomotor activity rhythms of C57/Bl6 mice under a chronic jet lag (CJL) protocol (ChrA(6/2) ), which consisted of 6-hour phase advances of the light-dark schedule (LD) every 2 days. Through periodogram analysis, we found 2 components of the activity rhythm: a short-period component (21.01 ± 0.04 h) that was entrained by the LD schedule and a long-period component (24.68 ± 0.26 h). We developed a mathematical model comprising 2 coupled circadian oscillators that was tested experimentally with different CJL schedules. Our simulations suggested that under CJL, the system behaves as if it were under a zeitgeber with a period determined by (24 - [phase shift size/days between shifts]). Desynchronization within the system arises according to whether this effective zeitgeber is inside or outside the range of entrainment of the oscillators. In this sense, ChrA(6/2) is interpreted as a (24 - 6/2 = 21 h) zeitgeber, and simulations predicted the behavior of mice under other CJL schedules with an effective 21-hour zeitgeber. Animals studied under an asymmetric T = 21 h zeitgeber (carried out by a 3-hour shortening of every dark phase) showed 2 activity components as observed under ChrA(6/2): an entrained short-period (21.01 ± 0.03 h) and a long-period component (23.93 ± 0.31 h). Internal desynchronization was lost when mice were subjected to 9-hour advances every 3 days, a possibility also contemplated by the simulations. Simulations also predicted that desynchronization should be less prevalent under delaying than under advancing CJL. Indeed, most mice subjected to 6-hour delay shifts every 2 days (an effective 27-hour zeitgeber) displayed a single entrained activity component (26.92 ± 0.11 h). Our results demonstrate that the disruption provoked by CJL schedules is not dependent on the phase-shift magnitude or the frequency of the shifts separately but on the combination of both, through its ratio and additionally on their absolute values. In this study, we present a novel model of forced desynchronization in mice under a specific CJL schedule; in addition, our model provides theoretical tools for the evaluation of circadian disruption under CJL conditions that are currently used in circadian research.
Authors:
Leandro P Casiraghi; Gisele A Oda; Juan J Chiesa; W Otto Friesen; Diego A Golombek
Related Documents :
4069944 - Kinetic occlusion by apparent movement.
2339514 - The temporal range of motion sensing and motion perception.
6458654 - Dimensions of figural identity and apparent motion.
7339574 - A new bistable motion illusion based upon 'kinetic optical occlusion'.
22465564 - Stimulus response latency of cough and expiration reflex depends on breathing in the ra...
20330964 - Observations of microbubble translation near vessel walls.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Journal of biological rhythms     Volume:  27     ISSN:  1552-4531     ISO Abbreviation:  J. Biol. Rhythms     Publication Date:  2012 Feb 
Date Detail:
Created Date:  2012-02-06     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8700115     Medline TA:  J Biol Rhythms     Country:  United States    
Other Details:
Languages:  eng     Pagination:  59-69     Citation Subset:  IM    
Affiliation:
*Laboratorio de Cronobiología, Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Quilmes, Argentina.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Rapid assessment of sleep-wake behavior in mice.
Next Document:  Human nonvisual responses to simultaneous presentation of blue and red monochromatic light.