Theses and Dissertations

Issuing Body

Mississippi State University


Elder, Steven H.

Committee Member

Simpson, Chartrisa LaShan

Committee Member

Eells, Jeffrey B.

Committee Member

Coolen, Lique

Date of Degree


Document Type

Graduate Thesis - Open Access


Biomedical Engineering

Degree Name

Master of Science (M.S.)


James Worth Bagley College of Engineering


Department of Agricultural and Biological Engineering


Female sheep exposed to excess testosterone (T) in utero display symptoms similar to those observed in women with polycystic ovarian syndrome (PCOS). Prenatal T-treated ewes display masculinized sexual behavior and increased food-reward seeking behavior. A neural substrate critical for these goal-directed behaviors is the dopaminergic system in the ventral tegmental area. We have recently shown that in adult ewes dopamine expression in the VTA is increased by prenatal T exposure. In this thesis, I tested the hypothesis that alterations of the VTA dopamine system by prenatal-T are caused via activation of androgen (AR) and/or insulin receptors (IR). Analysis of immunohistochemical staining shows an increase of tyrosine hydroxylase (TH) expression, AR, or IR, along with changes in co-expression of AR/TH and IR/TH. These changes were blocked or reversed by prenatal treatments with flutamide or rosiglitazone, or postnatal treatments with rosiglitazone or metformin, implicating AR and IR in alterations of the VTA