Meeting Abstract

P1.86  Wednesday, Jan. 4  Vitellogenin induction by PCBs in the turtle Trachemys scripta SMELKER, KS*; VALVERDE, RA; Southeastern Louisiana University; Southeastern Louisiana University

Vitellogenin (Vtg) detection is used as an indicator of the presence of endocrine disrupting chemicals, specifically estrogen-mimicking compounds, which are known to cause physiological and behavioral changes in otherwise healthy animals. Vtg is a precursor protein for yolk production in nonmammalian vertebrates. Liver production of Vtg is induced by estrogen stimulation and is normally found only in reproductively active females; however both males and females carry the gene necessary for Vtg production. Previous research shows that polychlorinated biphenyls (PCBs) are environmentally persistant estrogenic contaminants. The purpose of this study was to demonstrate that PCBs are capable of inducing Vtg production in red-eared slider turtles (Trachemys scripta). Fifteen turtles of varying size and sex and having no initial detectable Vtg, received 3 intraperitoneal injections of varying concentrations of PCBs. Blood samples were then analyzed using a western blot. Positive control turtles injected with Estradiol-17β and turtles that received 100µg PCBs/g body weight all showed Vtg induction. Two of three turtles that received 10µg PCBs/g body weight showed Vtg induction, and turtles injected with 1µg PCBs/g body weight did not show Vtg induction. These results indicate that turtles exposed to varying levels of PCBs demonstrate Vtg induction in a dose-response manner.