Meeting Abstract

30.3  Monday, Jan. 4  Correlation between differences in CRF levels and behavior in wild-trapped kangaroo rats CSIKAR, E.J.*; VALENTINO, R.J.; WALSBERG, G.E.; ASU; C.H.O.P.; ASU Ecsikar@asu.edu

In laboratory studies in which CRF was administered to animals in a novel environment, animals showed an increase in vigilance, a reduction in ambulatory movement, and increased levels of anxiety. One paradigm for anxiety is the open-field test which contrasts a rat’s innate curiosity to explore a novel environment with its desire to remain in a safe situation. In general, the anxiety level of the animal is inversely proportional to the amount of time spent exploring the center of the open field. Another model is the shock-prod paradigm, which measures the response of the animal to a mild electric shock. Generally, behaviors may be divided into two categories: active and passive. These experiments were conducted to examine behavioral consequences of observed differences in CRF in wild-trapped kangaroo rats from contrasting habitats. More specifically, animals from three sites (2 mesic/chaparral and 1 xeric/desert) were trapped, brought into captivity, maintained for 48 hours under standard small rodent housing conditions then individually run in the open field trial. Twenty-four hours after the open field trial, animals were individually run in the shock-prod trial. It was predicted that both groups of mesic animals would both be significantly different from their xeric counterpart; however, the results did not confirm this. Results indicate that animals from the most densely vegetated mesic site spent significantly more time in the center of the arena and spent a greater portion of time digging in the shock trial than animals from the second mesic site and the xeric site. Although unanticipated, the results are generally consistent with other research that indicates a switch from an active to a passive coping strategy when exposed to a chronic or severe stressor.