Differential effects of stress by sex and stress model: the source matters

It has been shown that stress is related to survival and adaptation. However, the same adaptive response can become noxious and produce disruptions that are related to the development of different disorders, such as anxiety, depression, post-traumatic stress disorder, etc. These dual effects of stress (positive/negative) could be related to the type of stress, intensity, and recently it has been shown that sex has a major role in the behavioral output. The goal of this study was to characterize the effects of the type of stressor on anxiety-like behaviors, depressive-like behaviors, and spatial and recognition memory. Male and female Wistar rats, 12 weeks old and weighing 200-340 g at the beginning of the experiment were used. The subjects were divided into control, Chronic Unpredictable Stress Battery (CUSB), and Predator Scent Stress (PSS) groups. They were evaluated using the following tests: open field, forced swim, elevated zero maze, saccharin preference, Barnes maze, and novel object recognition tests. The results revealed sex- and stressor-specific behavioral and neuroendocrine profiles, indicating that stress outcomes cannot be generalized without carefully considering the source of stress, the sex/gender of the subject, and other variables relevant to the pathophysiology of stress-related mental illnesses.