The roles of neurotransmission in development, neurophysiology and behavior
Mouse molecular genetics, electrophysiology, behavioral studies, molecular expression analysis
Broadly, the lab studies the development and physiology of the mammalian brain. One goal is to define the systems that contribute to specific behaviors, and to understand the mechanisms that underlie these behaviors. Such knowledge may ultimately permit the prevention and treatment of mental illness. Gene-targeting allows the analysis of specific genetic alterations in the context of the whole organism. The ability to add, delete or modify genes is particularly useful in the analysis of complex organ systems such as the brain, where half of all genes are thought to be uniquely expressed.
The lab focuses on the adrenergic nervous system in which norepinephrine (NE) and epinephrine are the classic neurotransmitters. By genetically eliminating the biosynthetic enzyme for NE, dopamine beta-hydroxylase (DBH), mutant mice (Dbh-/-) that completely lack NE and epinephrine were created. These mice are conditional mutants in that NE can be restored to the adrenergic terminals by supplying a synthetic amino acid precursor of NE, L-DOPS. The lab is pursuing several fundamental observations that resulted from the creation of these mutant mice. These include the roles of NE in learning and memory, as well as the neuronal physiology and signaling that underlie these effects. They also include the role of NE in the effects of stress. For each of these, potentially important interactions with other transmitters and hormones is also being explored. Finally, Dr. Thomas is pursuing several novel genetic approaches for producing complementary models to the Dbh-/- mice toward a more complete understanding of CNS adrenergic function.
Young, MB and Thomas, SA: M1-muscarinic Receptors Promote Fear Memory Consolidation via Phospholipase C and the M-current. J Neurosci 33: in press, 2013.
Zhang L, Ouyang M, Ganellin CR and Thomas, SA: The slow afterhyperpolarization: a target of beta1-adrenergic signaling in hippocampus-dependent memory retrieval. J Neurosci Page: 5006-16, 2013.
Ouyang, Y., Young, M.B., Lestini, M.M., Schutsky, K. and Thomas, S.A.: Redundant catecholamine signaling consolidates fear memory via phospholipase C. J Neurosci 32: 1932-41, 2012.
Schutsky, K., Ouyang, M., Castelino, C. B., Zhang, L. and Thomas, S. A.: Stress and glucocorticoids impair memory retrieval via β2-adrenergic, Gi/o-coupled suppression of cAMP signaling. J Neurosci 31: 14172-14181, 2011.
Schutsky, K., Ouyang, M. and Thomas, S. A.: Xamoterol impairs hippocampus-dependent emotional memory retrieval via Gi/o-coupled β2-adrenergic signaling. Learning & Memory 18: 598-604, 2011.
Murchison, C. F., Schutsky, K., Jin, S.-H. and Thomas, S. A.: Norepinephrine and β1-adrenergic signaling facilitate activation of hippocampal CA1 pyramidal neurons during contextual memory retrieval. Neuroscience 181: 109-116, 2011.
Ouyang M, Zhang L, Zhu JJ, Schwede F, Thomas SA: Epac is required for hippocampus-dependent memory retrieval. Proc Natl Acad Sci USA 105: 11993-11997, 2008.
Ouyang M and Thomas SA: A requirement for memory retrieval during and after long-term extinction learning. Proc Natl Acad Sci USA 102: 9347-9352, 2005.
Murchison CF, Zhang X-Y, Zhang W-P, Ouyang M, Lee A, Thomas S: A distinct role for norepinephrine in memory retrieval. Cell 117: 131-143, 2004.
Cryan JF, O’Leary OF, Jin S-H, Friedland JC, Ouyang M, Hirsch BR, Page ME, Dalvi A, Lucki, I Thomas SA: Norepinephrine-deficient mice lack responses to antidepressant drugs, including SSRIs. Proc Natl Acad Sci USA 101: 8186-8191, 2004.
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Last updated: 06/26/2013
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