Cardiac baroreflex sensitivity analysis

Bradycardic and tachycardic reflex responses produced by bolus infusion of phenylephrine (0.1 mg ml⁻¹, i.v.) and sodium nitroprusside (0.1 mg ml⁻¹, i.v.) (Sigma‐Aldrich Co., Poole, UK) were measured to generate baroreflex function curves, as reported previously (Abdala et al. 2012; Lincevicius et al. 2015). Values of matching systolic blood pressure (SBP) variations with reflex heart rate (HR) responses were plotted separately for each vasoactive drug to create linear regression curves for each group, and their slopes were compared to evaluate changes in baroreflex sensitivity (beats min^–1 mmHg^–1).