Priming effects of activity-stress ulcer in rats

The activity-stress ulcer procedure consists of housing rats in running-wheel activity cages while at the same time, restricting their food intake to 1 hr per day. Male Wistar rats which had been habituated with ad lib feeding to the running-wheel cage environment for 3 days prior to the restricted feeding phase, developed significantly more gastric glandular ulcers and exhibited greater levels of running activity when compared to rats which had been given no habituation experience. Control rats housed in standard laboratory cages but which received the same restricted feeding regimen, developed significantly less stress pathology. Since allowing to rats access to the running-wheel during habituation resulted in enhanced stress pathology, this manipulation is referred to as a "priming effect." A possible explanation for such a "priming effect" is discussed in terms of procedures which may increase running wheel activity and decreases survival time during the restricted feeding phase of the activity-stress ulcer procedure.