Chronic stress induces over-activation and dysfunction of stress-activated systems, resulting in further brain damage and depressive-like behavior. Depression is a potentially life-threatening disorder that affects people and, therefore, it is one of the most important public health problems. This study examined the effects of chronic restraint stress (CRS: 2 hours × 14 days) on the anxiety-like and depression-like behaviors in rats, as well as on the possible changes in the concentrations of dopamine (DA) and noradrenaline (NA) in the prefrontal cortex and hippocampus. We observed a decrease in the number of entries into open arms and time spent in open arms during the elevated plus-maze test (anxiety-like behavior), as well as the increased immobility during the forced swimming test (depression-like behavior). In addition, we found that CRS increases concentration of NA and decreases concentration of DA in the prefrontal cortex and hippocampus. Also, we recorded a significant correlation between the animal behavior and levels of neurotransmitters in the prefrontal cortex and hippocampus in stress conditions provoked by CRS. The results presented here suggest that there is a relationship between the animal behavior and levels of neurotransmitters in the prefrontal cortex and hippocampus in stress conditions provoked by CRS, which may be important in the research of numerous psychiatric diseases caused by chronic stress.

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