title: Folic Acid improves baroreceptor sensitivity in hypertension.
abstract: In hypertension baroreceptor-mediated modulation of heart rate is impaired, resulting in a decreased vagal control. Reactive oxygen species produced locally in the vasculature decrease baroreceptor sensitivity. Folic acid has antioxidant properties. Therefore, the aim of this study was to test whether folic acid improves baroreceptor function in hypertension. Twenty-one male patients with hypertension not taking any drugs for 2 weeks participated in the study and were randomized to folic acid 5 mg or matching placebo. Cardiac and vascular sympathetic baroreceptor functions were tested before and after a single dose of folic acid or placebo with two different methods: the alpha-coefficient method and the phenylephrine (PE) and sodium nitroprusside (SNP) bolus method. In the folic acid group both methods showed significantly improved cardiac and vascular sympathetic baroreceptor sensitivity compared with placebo. This study provides evidence that folic acid improves cardiac and vascular sympathetic baroreceptor sensitivity in hypertensive patients, which suggests an improved vagal control and an enhanced baroreceptor modulation of sympathetic vasomotor tone. Thus, folic acid may represent a novel treatment for prevention of orthostatic dysregulation and/or arrhythmic complications resulting from baroreceptor dysfunction.
authors.affiliation: Cardiovascular Center, Cardiology, University Hospital, Zürich, Switzerland. markus.bechir@ksb.ch
authors.forename: Markus
authors.initials: M
authors.lastname: Béchir
authors.forename: Frank
authors.initials: F
authors.lastname: Enseleit
authors.forename: Rémy
authors.initials: R
authors.lastname: Chenevard
authors.forename: Jörg
authors.initials: J
authors.lastname: Muntwyler
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Lüscher
authors.forename: Georg
authors.initials: G
authors.lastname: Noll
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D005492:Folic Acid / Q000494:pharmacology*; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects; D011311:Pressoreceptors / Q000187:drug effects* / Q000502:physiology; D013564:Sympathetic Nervous System / Q000187:drug effects / Q000503:physiopathology
chemical_list: D000975:Antioxidants; D005492:Folic Acid