Abstract
Adolescents naturally go to bed and awaken late, but are forced to awaken early for school and work. This leads to “social jetlag”, a state of circadian desynchrony (CD), in which internal biological rhythms are out of sync with behavioral rhythms. CD is associated with increased alcohol intake in adults, but has been less well-studied in adolescents. The goal of this study was to model adolescent alcohol intake during similar CD conditions in male C57BL/6J mice. Free access alcohol intake, water intake and wheel-running activity were measured during a normal 12HR photoperiod or during alternating photoperiod (Experiment 1: 12 h light for 4 days followed by 18 h light for 3 days, with dark (activity onset) delayed 9 h during the 18HR photoperiod; Experiment 2: 12 h light for 4 days followed by 6 h light for 3 days, with dark onset delayed 3 h during the 6HR photoperiod). In Experiment 1, CD produced a small but significant increase in the total alcohol intake per day as well as in intake in bouts, with the greatest increase over controls in the hours following the 6HR dark period. Additionally, the pattern of alcohol intake in bouts shifted to increase alcohol intake during the shorter dark period. In Experiment 2, the opposite effect occurred—the longer dark cycle led to lower alcohol drinking in the second half of the dark period. However, in Experiment 2, CD produced no significant changes in either total alcohol intake or alcohol intake in bouts. Conclusion: shifts in the light cycle that disrupt the regular pattern of day and night, and increase the length of the night phase, are sufficient to increase both drinking in bouts and restricted drinking in adolescent mice, modeling increased alcohol intake in adolescents during CD.
Highlights
Despite the laws, campaigns and preventive efforts of parents and physicians aimed at reducing underage drinking, alcohol abuse remains a major problem among adolescents in the United States
Adolescent alcohol consumption correlates with alcohol use disorder (AUD) later in life; 45% of adults who began drinking in adolescence meet the criteria for an AUD later in life (Hasin et al, 2007)
Unlike in our previous study in adult mice, we found that the mice in the experimental circadian desynchrony (CD) condition adapted rapidly to the changing light cycles, and their activity onsets only differed from controls on days 19–21, days 26–28, and days 33–35 (p < 0.05 between conditions), suggesting that adolescent mice phase-shifted within approximately one 24-h cycle of the light change
Summary
Campaigns and preventive efforts of parents and physicians aimed at reducing underage drinking, alcohol abuse remains a major problem among adolescents in the United States. Consuming alcohol under the age of 21 is illegal in the United States, the CDC reports that adolescents between ages 12 and 20 drink 11% of all alcohol consumed in the country, and over 90% of this is in the form of binge drinking (UDET, 2005). Adolescent alcohol exposure causes significant immediate and long-term consequences to both adolescents and their communities. It correlates with higher rates of academic problems, social problems and reckless behaviors including driving while intoxicated and drug use. A recent national survey reports that underage drinkers were more likely than persons aged 21 or older to report having used illicit drugs within 2 h of alcohol use on their last drinking occasion (19.0 vs 5.1 percent, respectively; Substance Abuse and Mental Health Services Administration, 2012). Adolescent alcohol consumption correlates with alcohol use disorder (AUD) later in life; 45% of adults who began drinking in adolescence meet the criteria for an AUD later in life (Hasin et al, 2007)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
