One can expect that in a group of alcoholics, the majority of them, if not all, also smoke cigarettes. Although the underlying causes are unclear, it has been suggested that because of the 'pleasure-enhancing effects' of nicotine, alcoholics in session tend to smoke. Well, another study provides another reason why such co-abuse is prevalent, and that is because nicotine also cancels out the sleep-inducing effects of alcohol.
As supported by previous research, over 85 percent of alcoholic adults in the US are also nicotine-dependent. This high prevalence is due to the fact that nicotine is an effective brain stimulant. Nicotine works in two ways: it awakens the basal forebrain to increase alcohol consumption, and it activates the nucleus accumbens to enhance the recreational sensation.
Just recently, additional action of nicotine was provided by a new study of a team of researchers from University of Missouri School of Medicine. They found that nicotine also stimulates a response in the basal forebrain to suppress sleep-promoting effects of alcohol.
Researchers used adult male rats with sleep-recording electrodes implanted to them. Each group was then treated with one of four combinations: alcohol and nicotine, alcohol and placebo, water and nicotine, and water and placebo. The nicotine dose was injected into the forebrain, while alcohol or water was injected into the stomach.
The statistical analysis revealed that while rats exposed to alcohol displayed strong sleep promotion, those treated with nicotine weakened the alcohol-induced sleepiness.
"One of the adverse effects of drinking alcohol is sleepiness," says Principal Author Mahesh Thakkar, Ph.D., associate professor and director of research in the MUSM's Department of Neurology in a press release. "However, when used in conjunction with alcohol, nicotine acts as a stimulant to ward off sleep. If an individual smokes, then he or she is much more likely to consume more alcohol, and vice-versa. They feed off one another."
By identifying the reactions that take place when people smoke and drink, it may be possible to curb alcohol and nicotine addiction. Moreover, having this knowedlge may also help improve the mental health of people with schizophrenia - with the disorder being so often associated with smoking.
The study appears in Journal of Neurochemistry.