Stress, Alcohol, and Hippocampal Genes

Abstract Alcohol dependence is a complex disorder which is influenced by factors such as stress and genotype. The complex relationship between stress and alcohol and its role in alcohol-use has yet to be elucidated. Both exposure to stress and alcohol-use cause gene expression changes in multiple brain regions including the hippocampus—an area vulnerable to alcohol and involved in the stress response. Most earlier studies have assessed gene expression changes in the hippocampus after exposure to these factors individually and found overlapping altered molecular pathways. In contrast, recent research examining differential gene expression in the hippocampus after exposure to the combination of ethanol and stress have found genetic networks distinct from those identified after exposure to each factor separately. This chapter aims to review gene expression differences in the hippocampus after stress or ethanol, and discusses bioinformatic methodology in the context of further analyzing a gene that is differentially expressed only after the combination of stress and alcohol exposure. This methodology has previously been used in microarray studies to identify genetic networks involved in the interaction of stress and ethanol.