Research in the Behavioral Neuropharmacology Laboratory examines the neurobiological effects of exercise in rodent models. The work focuses on how exercise produces long-term regulation of neurotransmitter functions and how these changes mediate the behavioral and neurobiological effects of exercise. Some of the experiments measure exercise-induced increases in the expression of the gene encoding galanin, a peptide neurotransmitter abundantly expressed in noradrenergic neurons. Other experiments measure brain-derived neurotrophic factor gene expression in the hippocampus. The overall aim is to understand how these neurotransmitters/trophic factors may contribute to the beneficial effects of exercise on brain function. Previous research has examined the neurobiological basis for the antidepressant and anti-stress effects of exercise. Other projects have studied the cognition-enhancing and neuroprotective effects of exercise. The laboratory is currently working on an NIH-funded project to study the role of exercise-induced increases in galanin on cocaine self-administration in rodent models of addiction and relapse. Techniques employed in the Holmes laboratory include in situ hybridization histochemistry to measure gene expression in the brain, stereotactic surgery, in vivo voltammetry and microdialysis, and a variety of behavioral paradigms including rodent models of stress, depression, and addiction.