Parallelism among stress effects on ulcer, immunosuppression and analgesia: commonality of mechanisms?

Some general principles and mechanisms have been discovered that govern proactive effects of one stress on animals' later stress or challenge induced behavior, nociception, immune function, and stomach ulcerations. As described below, these principles demonstrate a considerable degree of parallelism across the domains represented by measures of learning deficits and fear-related behaviors, hypoalgesia, immunological status and stress gastric ulcerations. At a minimum, these parallels suggest that operational factors found important in one domain are likely factors of importance in the other domains. Beyond this, these parallels are permissive of an inference of commonality in underlying processes. Nonetheless, results reviewed below suggest that the specific response of the organism to stress is highly dependent on specific characteristics of the stressor.