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bioRxiv · 10.1101/2020.03.04.977033

Fluoxetine treatment prevents cardiovascular changes in baroreflex and chemoreflex in rats subjected to chronic stress

Abstract

Stress may influence the autonomic regulation, pathogenesis of cardiovascular disease and play an important role in animal behavior as depression. Depression is evidenced as a significant risk factor for cardiovascular changes. This is of great importance as some studies show an association between symptoms of depression and increased risk of cardiovascular disease (CVD) morbidity. Additionality, those alterations can be alleviated by use of antidepressants such as fluoxetine, which is a selective serotonin reuptake inhibitor (SSRIs). The link between depression and cardiovascular changes is known to be mediated in part by autonomic mechanisms that contribute to the regulation of cardiovascular function. However, studies on the effects of SSRIs on cardiovascular autonomic function are inconsistent. Thus, in the present study we investigated, in adult male rats, the effect of chronic and acute treatment with fluoxetine on changes in autonomic mechanisms of baroreflex and chemoreflex induced by the repeated restraint stress (RRS) or chronic variable stress (CVS) on baroreflex and chemoreflex in a protocol of 14 days of stress sessions. The results found demonstrated that exposure to chronic stress (RRS and CVS) promove changes on cardiovascular and ventilatory responses controlled by autonomic reflexes, such as baroreflex and chemoreflex. Additionality, that chronic fluoxetine treatment for 21 days was able to prevent not only anhedonic behavior, but also of autonomic changes cardiovascular induced by chronic stress. Taken together, our results show that pharmacological treatment with fluoxetine may be also helpful to prevent cardiovascular events on account of depressive states, by correcting alterations in autonomic function.

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BibTeXRIS

Firmino, E. M. S., Kuntze, L. B., Lagatta, D. C., Dias, D. P. M., Resstel, L. B. M.. 2020-03-05. Fluoxetine treatment prevents cardiovascular changes in baroreflex and chemoreflex in rats subjected to chronic stress. https://doi.org/10.1101/2020.03.04.977033

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