Reduction of the cAMP response to norepinephrine in rat cerebral cortex following repeated restraint stress

The present studies examined the effect of restraint stress on the sensitivity of the catecholamine-cAMP generating system in the rat cerebral cortex. Restraint was found to cause a persistent reduction in the magnitude of the cAMP response to catecholamines. This effect occurred after repeated but not acute stress and was more marked with twice-daily as compared to once-daily treatment. The reduction in response was more marked with norepinephrine than with isoproterenol, indicating a selective action of stress on the non-beta component of the noradrenergic response. The findings suggest that subsensitivity of the cAMP response to norepinephrine is a general response to chronic stressful stimuli and may be related to the action of certain antidepressant agents.