title: Chronic Alcohol Consumption in Rats Leads to Desynchrony in Diurnal Rhythms and Molecular Clocks.
abstract: BACKGROUND
  Circadian rhythms are essential for adapting to the environment. Chronic alcohol consumption often leads to sleep and circadian disruptions, which may impair the life quality of individuals with alcohol use disorders and contribute to the morbidity associated with alcoholism.
  
  
  METHODS
  We used a pair-feeding liquid diet alcohol exposure protocol (6 weeks duration) in PER1::LUC transgenic rats to examine the effects of chronic alcohol exposure on: (i) diurnal rhythms of core body temperature and locomotor activity, (ii) plasma corticosterone (CORT) concentrations, and (iii) rhythms of ex vivo Period1 (Per1) expression in the suprachiasmatic nucleus (SCN), pituitary, and adrenal glands. We followed multiple circadian outputs not only to examine individual components, but also to assess the relative phase relationships among rhythms.
  
  
  RESULTS
  We found that chronic alcohol consumption: (i) reduced 24-hour body temperature and locomotor activity counts in the dark period, (ii) advanced the acrophase of diurnal rhythms of body temperature and locomotor activity, (iii) abolished the phase difference between temperature and activity rhythms, (iv) blunted and advanced the diurnal CORT rhythm, and (v) advanced Per1 expression in the adrenal and pituitary glands but not in the SCN. We found that chronic alcohol altered the phase relationships among diurnal rhythms and between the central (SCN) and peripheral (adrenal and pituitary) molecular clocks.
  
  
  CONCLUSIONS
  Our findings suggest that desynchrony among internal rhythms is an important and overlooked aspect of alcohol-induced circadian disruptions. The misalignment of phases among rhythms may compromise normal physiological functions and put individuals with chronic alcohol use at greater risk for developing other physical and mental health issues. How this desynchrony occurs and the extent to which it participates in alcohol-related pathologies requires further investigation.
authors: Programs in Neuroscience, Department of Integrative Physiology and Neuroscience, College of Veterinary Medicine, Washington State University, Pullman, Washington.
authors: Rong
authors: R
authors: Guo
authors: Programs in Neuroscience, Department of Integrative Physiology and Neuroscience, College of Veterinary Medicine, Washington State University, Pullman, Washington.
authors: Steve M
authors: SM
authors: Simasko
authors: Programs in Neuroscience, Department of Integrative Physiology and Neuroscience, College of Veterinary Medicine, Washington State University, Pullman, Washington.
authors: Heiko T
authors: HT
authors: Jansen
mesh_terms: D000311:Adrenal Glands / Q000737:chemistry; D000428:Alcohol Drinking / Q000009:adverse effects*; D000818:Animals; D001831:Body Temperature / Q000187:drug effects; D002940:Circadian Rhythm / Q000187:drug effects*; D003345:Corticosterone / Q000097:blood; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D056950:Period Circadian Proteins / Q000032:analysis; D010902:Pituitary Gland / Q000737:chemistry; D051381:Rats; D055647:Rats, Transgenic; D017208:Rats, Wistar; D013493:Suprachiasmatic Nucleus / Q000737:chemistry
chemical_list: C539024:Per1 protein, rat; D056950:Period Circadian Proteins; D003345:Corticosterone
keywords: Chronic Alcohol; Circadian Rhythms; Desynchrony; Hypothalamic-Pituitary-Adrenal Axis; Period1