Meeting Abstract

P2.163  Thursday, Jan. 5  Stress-induced behavioral changes are not mediated by corticosterone in red-legged salamanders WACK, Corina L*; RATAY, Mary K.; WOODLEY, Sarah K.; Chowan University, Murfreesboro, NC; Duquesne University, Pittsburgh, PA; Duquesne University, Pittsburgh, PA wackc@chowan.edu

In most vertebrates, exposure to stressors can cause changes in physiology (i.e. immune function) and behavior (i.e. reproduction). These changes may be mediated by plasma glucocorticoids (GCs), which also increase when animals are exposed to stressors. To further understand stress effects on behavior, we tested the hypothesis that stress-induced changes in locomotor activity in the red-legged salamander (Plethodon shermani) are mediated by increase in plasma corticosterone (CORT), the primary GC of most vertebrates. We conducted three experiments. In the first experiment, salamanders were handled. Handling was designed to mimic capture by a predator and is a standard protocol for eliciting increased GCs. Forty-five minutes after the onset of handling, locomotor activity was recorded. In the second experiment, a non-invasive dermal patch containing CORT (2.5 ug) was administered and locomotor activity was assessed approximately two and 24 hours later. In the third experiment, two doses of CORT (0.63 and 2.5 ug) were administered via dermal patches to subjects, and locomotor activity was assessed 0.5 and 12 hours after patch removal. Although handling decreased locomotor activity, neither high nor low doses of corticosterone altered locomotor activity compared to controls at any time point. These data suggest that stress-induced changes in locomotor activity are not mediated by CORT.