Source: Contra Costa Times Published: Tuesday, June 10, 1997 Section: Fitness: Page F3 Contact: Scientists study nicotine's powerful hold on the brain By SUSAN KREIMER KNIGHT.RIDDER NEWSPAPERS Debra Smith is craving to break her bondage to cigarettes. In the morning, after parking her car in front of her workplace, she lights up while listening to spiritual tapes on which ministers preach about breaking any bad habit. "It's something you don't want," the 36yearold bookkeeper said of her smoking addiction. "You want to get rid of it. It's not good for you." In her 21 years of puffing, Smith, of Cedar Lake, md., has tried to quit seven or eight times. Her most successful attempt lasted three months. As scientists discover more about nicotine's powerful hook on the brain, they are better able to explain why the will to quit may not be enough to keep Smith and other smokers away from cigarettes. The research into nicotine addiction continues at a time when 29 states have multibilliondollar health claims pending against the tobacco industry. Former smokers and their families have also sued tobacco giants, charging that cigarettes caused them to become ill. And while one family last year won a $750,000 judgment against a cigarette company, in May, a jury in Jacksonville, Fla., found R.J. Reynolds Tobacco Co. not ]iab]e for the death of a 49yearold woman who died in 1995 after a lifetime of smoking. Meanwhile, researchers studying the effects of nicotine on health have found that it indeed alters brain chemistry And that may explain why withdrawal symptoms like headaches, nervousness and irritability make smoking a difficult habit to kick. "Nicotine is taken up very rapidly in the brain," said Dr. Edythe London, head of the brainimaging center at the National Institute on Drug Abuse in Bethesda, Md. Traveling twice as quickly through the bloodstream as mainlined heroin, nicotine reaches the brain "within seven seconds of a drag," said Susan Adrians, a chemical dependency therapist in the department of behavioral medicine at St. Margaret Mercy Healthcare Centers South Campus in Dyer, md. Within a halfhour of smoking a cigarette, Adrians said, the nicotine level "drops off slightly and the cravings set in." After a person begins smoking, nicotine hinds to specific receptors in the brain, changing its chemistry, experts say. "A receptor is the equivalent of a biological keyhole (with nicotine being the key)," said Dr. Jack Henningfield, associate professor at Johns Hopkins Medical School in Baltimore. "Nicotine exposure causes the body to end up with an increased number of nicotine receptors," Henningfield said. The brain then becomes accustomed to a continual level of nicotine, and its pleasureinducing effects contribute to dependence, brain researcher London said. "Without the nicotine, there's an imbalance. So there are some behavioral effects," she said.