Assistant Professor
B.S., M.S. University of Wyoming
Ph.D. Arizona State University
Postdoctoral Fellow, University of Bristol, United Kingdom
Schroeder Complex 429A
(414) 288-4534
E-mail
Neurobiology of Stress: Cellular mechanisms underlying stress hormone action
Work in my laboratory is focused on understanding the mechanisms by which stress alters brain function. Stress leads, in all vertebrates, to the release of corticosteroid hormones. These hormones exert powerful neuromodulatory effects that lead to context- and state-dependent alterations in ongoing behavioral and physiological processes. The primary goals of my research are to identify mechanisms by which corticosteroids alter cognitive function, motivation, sensory processing, and nueroendocrine responses, leading to adaptive responses to acute stress; and to understand how these mechanisms may be involved in the pathophysiology of stress-related disorders including depression, generalized anxiety disorder, post-traumatic stress disorder and drug abuse.
One mechanism by which corticosteroids can alter behavioral and physiological processes is by modulating the actions of monoamine neurotransmitters (serotonin, dopamine, noradrenaline, adrenaline, and histamine). I have been studying the role of organic cation transporter 3 (OCT3), a multispecific monoamine transporter that is directly inhibited by corticosteroid hormones, in mediating stress-induced alterations in monoaminergic signaling. I use a variety of cellular, molecular, and behavioral tools to examine the effects of corticosteroids on extracellular concentrations of monoamines in specific brain regions, and to relate these effects to alterations in monoamine-dependent behaviors.
Selected References:
Gasser, P.J., Orchinik M., Lowry C.A., (in preparation) Distribution of organic cation transporter 3, a corticosterone-sensitive monoamine transporter, in the rat brain.
Lowry C.A., Evans, A.K., Gasser, P.J., Hale, M.W., Staub, D.R., Shekhar, A. Topographical organization and chemarchitecture of dorsal raphe nucleus and the median raphe nucleus. In "Serotonin and sleep: Molecular, Functional and Clinical Aspects. J. Monti, S. Pandi-Perumal, B. Jacobs, D. Nutt, eds. Birkhauser Verlag AG, Basel, Switzerland, Submitted June 2007.
Gasser, P.J., Orchinik, M. (2007) Vasopressin-induced translocation and proteolysis of protein kinases
Cα in amphibian brain: modulation by corticosterone. Brain Res. 1134 (1): 18-26.
Gasser, P.J., Lowry C.A., Orchinki, M. (2006) Corticosterone-sensitive monoamine transport in the rat dorsomedial hypothalamus: potential role for organic cation transporter 3 in stress-induced modulation of monoaminergic neurostransmission. J. Neurosci., 26 (34): 8758-8766.
Orchinik, M. Gasser, P.J., Breuner, C.W. (2002) Rapid Corticosteroid Actions on Behavior: Cellular Mechanisms and Organismal Consequences. In "Hormones, Brain, and Behavior", D. Pfaff, ed. pp. 567-600. Academic Press, San Diego.
Orchinik, M., Matthews L., Gasser P.J. (2000) Distinct specificity for corticosteroid binding sites in amphibian cytosol, neuronal membranes, and plasma. Gen. Comp. Endocrinol. 118: 284-301.
Gasser, P.J., Orchinik, M. (2002) Membrane Glucocorticoid Receptors. In: "The Encyclopedia of Stress", Vol 2., G. Fink, ed. pp. 713-721. Academic Press, San Diego.
