Washington, Sep 1 (Inditop.com) Chronic alcohol consumption blunts the biological clock’s ability to synchronise daily activities with light, even days after the drinking ends, according to a new study.
The study describes the changes that drinking can produce on the body’s masterclock and how it affects behaviour. The research provides a way to study human alcoholism using an animal model, said researcher Christina L. Ruby of the University of Tennessee (UTE).
Alcohol consumption affects the master clock located in the brain. This clock controls the circadian cycle, a roughly 24-hour cycle, which regulates sleeping and waking, as well as the timing of a variety of other physiological functions, such as hormonal secretions, appetite, digestion, activity levels and body temperature.
Researchers used hamsters (a rodent species) to find out how alcohol affects circadian rhythms. Although hamsters are nocturnal, light synchronises their clocks, just as with humans.
The animals were divided into three groups. The control group received water only. A second group received water containing 10 percent alcohol and the third group received water containing 20 percent alcohol. Hamsters, when given a choice, prefer alcohol, which they metabolise quickly.
The animals drank as much as they wanted and lived in an environment that provided 14 hours of light and 10 hours of darkness each day.
Hamsters that drank alcohol had the hardest time shifting their rhythms after exposure to the dim light, and the more alcohol they drank, the harder it was to adjust.
Exposure to dim light caused the water-only hamsters to wake up 72 minutes earlier than they normally would. The 10 percent alcohol group woke up 30 minutes earlier and the 20 percent alcohol group woke up only 18 minutes earlier.
Exposure to bright light helped the alcohol-consuming hamsters to wake up sooner, greatly reducing the difference in wake up times among the groups. The control animals woke up 102 minutes earlier compared to the 20 percent alcohol group that woke up 84 minutes earlier.
The researchers aim to apply the research to people, who also show circadian disruptions from drinking, said an UTE release.
These results appear in the American Journal of Physiology.
