Dr. William Corrigall described the neurobiological targets of current research: genes and gene products that play a role in structure and response of nicotinic receptors, and neurochemical systems, which are modulated by dopamine, GABA, serotonin, and glutamate.

Dr. Caryn Lerman of the University of Pennsylvania described studies exploring the effect of genetic variations on the activity of enzymes that play a role in nicotine metabolism. This research suggests a potentially valuable role for medications that mimic the effect of genetic variants associated with lower rates of smoking initiation, reduced impact of nicotine on the brain’s dopamine system, and decreased craving among smokers who try to quit.

Dr. Marina Picciotto of Yale University discussed research that has expanded the understanding of the role of nicotine receptors—the sites at which nicotine acts on brain cells. Scientists have identified two subtypes of these receptors and a total of 12 different forms within the subtypes. Each receptor structure contains 5 components including some combination of these 12 forms. Researchers now are investigating the possibility that the subtly different functions of receptors with different combinations of subtypes may represent new targets for medications to block or counteract nicotine’s effects in the brain.