Prenatal exposure to nicotine appears to inflict lasting damage
that may leave the brain vulnerable to further injury and
addiction upon later use of the drug, according to animal
research conducted by Duke University Medical Center
pharmacologists. The researchers found in rat studies that
exposure to nicotine in fetal development alters the brain
structures and brain cell activity in regions critical to
learning, memory and reward. In turn, those changes influence
nicotine's effects on the brain during adolescence, a time when
many smokers first take up the habit, the team found. The study
in rats might provide a biological explanation for the high
incidence of smoking among teens whose mothers smoked during
pregnancy, the researchers said. "Teens whose mothers smoked
during pregnancy can show signs of nicotine dependence and
withdrawal after just a handful of cigarettes," said Theodore
Slotkin, professor of pharmacology, psychiatry and neurobiology
at Duke. "Our study suggests a biological mechanism to exp