Acetaldehyde, one of the main chemical components of tobacco smoke, appears to increase the addictive properties of nicotine, according to animal studies conducted by the UC Irvine Transdisciplinary Tobacco Use Research Center (TTURC).
In addition, the researchers found that adolescents are most vulnerable to the rewarding effects of the nicotine-acetaldehyde combination.
Study results appear in the online version of Neuropsychopharmacology.
Nicotine is the primary chemical in cigarette smoke that causes addiction, yet when tested in animal studies, the draw of nicotine alone appears to be relatively weak compared to other abused drugs. Surprised by this phenomenon, UCI researchers conducted a series of studies in rodents to determine whether nicotine may interact with some of the other 4,000 components of tobacco smoke to enhance addictiveness.
“We chose to study acetaldehyde because it is a major component of tobacco smoke, present in a one-to-two ratio to nicotine,” said James Belluzzi, lead researcher and adjunct professor of pharmacology in the UCI College of Medicine. “Additionally, there is evidence that acetaldehyde may play a role in alcohol addiction.”
Belluzzi, researcher Ruihua Wang and Frances Leslie, professor of pharmacology and TTURC director, evaluated possible acetaldehyde and nicotine interactions in a rigorous self-administration test. Adolescent and adult male rats were tested in a procedure during which each nose poke by the rodents delivered acetaldehyde or nicotine, a combination of both drugs, or saline.