Fox odour affects corticosterone release but not hippocampal serotonin reuptake and open field behaviour in rats

Group-housed Sprague-Dawley (SD) rats exposed for 1 h to 2,5-dihydro-2,4,5-trimethylthiazoline (TMT, a component of fox feces) did not display changes in hippocampal serotonin (5-HT) metabolism and [3H]5-HT reuptake, compared to water or butyric acid. Such an observation extended to isolated SD and Fischer 344 rats. When group-housed SD rats were tested 1 week after a 1-h exposure to TMT, hippocampal 5-HT metabolism, [3H]5-HT reuptake, and [3H]paroxetine binding at the 5-HT transporter remained unchanged. This study questions TMT as a specific predatory stimulus as both butyric acid and TMT increased plasma corticosterone levels whilst leaving intact open field behaviour (at least in group-housed SD rats).