Ovarian failure induced by 4-vinylcyclohexene diepoxide worsens the autonomic cardiovascular response to chronic unpredictable stress in rats

Publication date: 1 June 2019Source: Life Sciences, Volume 226Author(s): Flaviano Lorenzon, Bruna B. Simas, Tamires Gregorio, Janete A. Anselmo-Franci, Cilene Lino de Oliveira, Domitila A. Huber, Fernanda B. LimaAbstractAimsAfter menopause, women are more responsive to stress and more prone to exhibit hypertension, which elevates the risk of cardiac diseases. This vulnerability is due, in part, to the decline of ovarian steroids plasma levels. The 4-vinylciclohexane diepoxide (VCD) causes a gradual depletion of ovarian follicles causing loss of the normal ovarian function and a hormonal profile comparable to menopause in humans. We aimed to verify whether the ovarian failure (OF) worsens the cardiovascular autonomic response to stress.Main methodsRats were treated with VCD (160 mg/kg) or oil for 15 days, exposed to chronic unpredictable stress (CUS) for 10 days and studied 80 and 180 days after VCD treatment.Key findings80 days after VCD-treatment, stressed rats showed increased sympathetic nerve activity, reduced parasympathetic activity and an increase in the overall spontaneous baroreflex sensitivity (BRS). 180 days after VCD treatment, BRS was impaired and the vascular sympathetic activity was increased, independently of stress exposure.SignificanceNeither 80 nor 180 days after the onset of VCD-treatment the hypertensive effects of stress were enhanced in rats. However, OF led to a worsening on different aspects of the cardiovascular response to stress, whic...
Source: Life Sciences - Category: Biology Source Type: research