Effects of time-of-day and photoperiod phase shifts on voluntary ethanol consumption in rats.
Two experiments were conducted to examine the circadian fluctuations in voluntary ethanol (ETOH) consumption in male Sprague-Dawley rats conditioned to consume ETOH in their homecage and exposed to photoperiod phase shifts equivalent to those experienced by humans. Using a maintenance concentration of 20% w/v ETOH, changes in homecage drinking in 42 rats were assessed after photoperiod phase shifts similar to those inducing "jet lag" in humans and after experimenter-induced "hangover." A single 8-hr photoperiod phase advance significantly increased ETOH intake for three consecutive days, and a single photoperiod phase-delay increased intake only on the day of the phase shift. Acute ETOH withdrawal significantly reduced the voluntary consumption of ETOH for two consecutive days. In a second group of 30 rats maintained to consume a lower concentration of 10% w/v ETOH, the long-term effects of "shift lag" initiated by repeated photoperiod phase shifting similar to those experienced by humans working under a rotating work schedule were examined. Significant increases in intake occurred over the 2-month testing period. The significant alterations in voluntary intake initiated by the shift work schedule was related to the significant changes in blood alcohol concentrations.
Gauvin
D V
DV
Department of Psychiatry and Behavioral Sciences, University of Oklahoma Health Sciences Center, Oklahoma City 73190-3000, USA.
Baird
T J
TJ
Vanecek
S A
SA
Briscoe
R J
RJ
Vallett
M
M
Holloway
F A
FA
D000428:Alcohol Drinking / Q000503:physiopathology*; D000437:Alcoholism / Q000503:physiopathology; D000818:Animals; D002940:Circadian Rhythm / Q000502:physiology*; D000431:Ethanol / Q000009:adverse effects / Q000493:pharmacokinetics; D006801:Humans; D008027:Light; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013375:Substance Withdrawal Syndrome / Q000503:physiopathology; D014940:Work Schedule Tolerance
D000431:Ethanol