We tested our hypothesis that noradrenaline is released in the hippocampus by colorectal distention of rats, and that it induces pain-related behavior. Noradrenaline levels with colorectal distention were significantly higher than those with restraint stress and free moving. Abdominal contractions were induced only by colorectal distention. Our results suggest that noradrenaline levels increase in the hippocampus under colorectal distention and this may relate to behavioral changes.