Cardiovascular outcomes related to social defeat stress: New insights from resilient and susceptible rats

Publication date: Available online 6 June 2019Source: Neurobiology of StressAuthor(s): Gessynger Morais-Silva, Willian Costa-Ferreira, Lucas Gomes-de-Souza, Jacqueline C. Pavan, Carlos C. Crestani, Marcelo T. MarinAbstractStress exposure is an important risk factor for psychiatric and cardiovascular disorders. Two phenotypes related to coping with stress can be observed in rodents that experience chronic social defeat stress (SDS): susceptible, showing social avoidance and behavioral changes related to depression, and resilient, showing none of these alterations. Moreover, a strong correlation exists between depression and the development of or mortality due to cardiovascular diseases. Nevertheless, little is known about cardiovascular alterations related to SDS exposure in those phenotypes or their correlation with depressive-like behaviors. Using a chronic SDS protocol followed by the social interaction test, we identified Wistar rats as resilient or susceptible to SDS. Susceptible animals showed increased depressive-like behaviors with resting tachycardia and decreased heart rate variability (HRV) due to increased sympathetic tone in the heart and a less effective baroreflex. In contrast, resilient rats were protected from these alterations by increased vagal tone, resulting in greater HRV values. To our knowledge, our study is the first to indicate that harmful cardiovascular outcomes are related to depressive-like behaviors in susceptible rats and to suggest a mechanism ...
Source: Neurobiology of Stress - Category: Neuroscience Source Type: research