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Mental and Addictive Disorders
SHANNON G. MATTA, Ph.D.
Address
Education
Research InterestsNicotine’s multiple effects on neuroendocrine and motivated behavioral responses are the research foci of this lab. Investigations into neuroendocrine effects focus on nicotine's actions on the stress-responsive systems of the brain, including the classical hypothalamo-pituitary-adrenal axis, as well as extrahypothalamic forebrain regions and brainstem catecholaminergic regions that modulate this axis. In addition, Dr. Matta was a co-developer of a novel self-administration animal (rat) model for nicotine exposure that more closely approximates human nicotine consumption - i.e., exposure is truly chronic, intermittent and motivated. This behavioral model is the underpinning to studies designed 1) to determine individual sensitivity to drug-taking behavior, 2) to elucidate the mechanisms by which nicotine (like cocaine, amphetamine and other drugs of abuse) activates and maintains the reward neurocircuitry, leading to dependence and addiction, and 3) to investigate the anecdotal property of chronic nicotine in alleviating anxiety and stress. Drug-induced neuronal plasticity, as indicated by alterations in gene expression in relevant brain regions after such chronic motivated nicotine exposure, also is under investigation. Finally, our most recent emphasis has been on investigations into neuronal plasticity resulting from the combined gestational exposure to nicotine and alcohol - an all-too-common circumstance in the human population. This gestational drug exposure results in vulnerability to enhanced drug-taking behavior in both adolescent and young adult offspring, which may identify a risk factor for human offspring of mothers who smoked and drank, even to just a moderate degree, during pregnancy. All these studies use in vivo microdialysis for real-time measurement of the release of monoamines (norepinephrine, dopamine, serotonin) and excitatory/inhibitory amino acids (glutamine, GABA) from specific brain regions in response to nicotine, other agonists, and/or antagonists in alert, behaving animals. These neuropharmacological studies are integrated with neuroanatomical methods to identify the neuronal pathways activated by nicotine and to characterize the specific receptor subtypes involved, both at pre- and post-synaptic sites. Primary methodologies include in vivo microdialysis, HPLC with electrochemical detection, immunocytochemistry, in situ hybridization, confocal microscopy and image analysis, laser capture microdissection, stereotaxic neurosurgery, vascular cannulation, gestational drug exposure paradigms, and models of motivated behavior. LinksRecent Publications
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