Toni Pak, Ph.D.

Professor, Departmental Chair

Professional Background
B.S., Environmental Population and Organismic Biology
University of Colorado, Boulder, CO

M.S.,  Secondary Science Education
University of Colorado, Boulder, CO

Ph.D., Neuroscience
University of Colorado, Boulder, CO

Postdoctoral Training
Colorado State University, Fort Collins, CO
Dept. of Biomedical Sciences
Dr. Robert J. Handa

Pak Lab Members
Jennifer Chang, PhD - Research Associate
Chun Kim - Graduate Student
Sarah Flury - Graduate Student
Mengjie Zhang - Research Technician 
Kyle Bartelt - Medical Student


Our Research

The central theme of our research focuses on the molecular signaling mechanisms and target genes of nuclear steroid receptors. Elucidating the molecular basis of nuclear steroid receptor-mediated gene expression is critical to understanding how steroid hormones modulate a variety of physiological processes including social behaviors, sexual maturation and senescence, reproductive function, and stress responses. Currently in my laboratory I have two distinct, but related, NIH-funded research projects. The first project focuses on defining and identifying novel molecular signaling mechanisms that facilitate estrogen independent activation of ER in neurons during menopause. We have evidence to suggest that ER alters its mode of action depending on the bioavailability of estrogen, raising the possibility that during the normal aging process ER differentially regulates its target genes. The second project focuses on identifying the interactive effects of alcohol and estrogen on AVP during pubertal development in order to better understand why women are predisposed to increased risk of anxiety disorders.

Select Publications

Mott NN and Pak TR (2012). Characterization of the human estrogen receptor beta splice variants in neuronal cells, J. Neuroendocrinology, In Press.

Przybycien-Szymanska MM and Pak TR (2012).  Estradiol is required for the sexually dimorphic effects of repeated binge-pattern alcohol exposure on the HPA axis during adolescence.  PLoS ONE, 7(2):e3226, PMCID: PMC3284554.                

Przybycien-Szymanska MM and Pak TR (2011).  Alcohol dysregulates corticotropin-releasing-hormone (CRH) promoter activity by interfering with the negative glucocorticoid response element (nGRE). PLoS ONE 6(10):e26647, PMCID: PMC3200354

Przybycien-Szymanska MM, Mott NN, Paul CR, Gillespie RA, and Pak TR (2011).  Binge-pattern alcohol exposure during puberty induces long-term changes in HPA axis reactivity.  PLoS ONE Apr 13;6(4):e18350, PMCID: PMC3076381.

Rao YS, Mott NN, Pak TR (2011) Effects of kisspeptin on parameters of the HPA axis.  Endocrine.  39(3):220.

Mott NN, Chung WCJ, Tsai, PS, Pak TR (2010) Differential fibroblast growth factor 8 (FGF8)-mediated autoregulation of its cognate receptors, Fgfr1 and Fgfr3, in neuronal cell lines. PLoS ONE 12;5(4):e10143.

Przybycien-Szymanska MM, Rao RS, Pak TR (2010) Binge-pattern alcohol exposure during puberty induces sexually dimorphic changes in genes regulating the HPA axis. Am J Physiol Endocrinol Metab 298:320-328.

Pak TR, Chung WCJ, Hinds LR, Handa RJ. (2009) Arginine vasopressin regulation in pre- and post-pubertal male rats by the androgen metabolite 3-Diol. Am J Physiol Endocrinol Metab 296(6):1409-1413.

Pak TR, Chung WCJ, Hinds, LR, Handa RJ (2007) Estrogen receptor-β mediates DHT-induced stimulation of the arginine vasopressin promoter in neuronal cells. Endocrinol. 148:3371-3382.

Pak TR, Chung WCJ, Roberts JL, Handa RJ (2006) Ligand-independent effects of estrogen receptor beta on mouse gonadotropin releasing hormone (GnRH) promoter activity. Endocrinol. 147(4):1924-1931.

Other Publications