title: Dysfunctional vestibular system causes a blood pressure drop in astronauts returning from space.
abstract: It is a challenge for the human body to maintain stable blood pressure while standing. The body's failure to do so can lead to dizziness or even fainting. For decades it has been postulated that the vestibular organ can prevent a drop in pressure during a position change--supposedly mediated by reflexes to the cardiovascular system. We show--for the first time--a significant correlation between decreased functionality of the vestibular otolith system and a decrease in the mean arterial pressure when a person stands up. Until now, no experiments on Earth could selectively suppress both otolith systems; astronauts returning from space are a unique group of subjects in this regard. Their otolith systems are being temporarily disturbed and at the same time they often suffer from blood pressure instability. In our study, we observed the functioning of both the otolith and the cardiovascular system of the astronauts before and after spaceflight. Our finding indicates that an intact otolith system plays an important role in preventing blood pressure instability during orthostatic challenges. Our finding not only has important implications for human space exploration; they may also improve the treatment of unstable blood pressure here on Earth.
authors.affiliation: Antwerp University Research center for Equilibrium and Aerospace, Dept. of Biomedical Physics, University of Antwerp, Belgium.
authors.forename: Emma
authors.initials: E
authors.lastname: Hallgren
authors.affiliation: Université libre de Bruxelles &Erasmus Hospital, Department of Cardiology, Laboratory of Physics and Physiology, Brussels, Belgium.
authors.forename: Pierre-François
authors.initials: PF
authors.lastname: Migeotte
authors.affiliation: Laboratory of Vestibular Physiology, Institute of Biomedical Problems of the Russian academy of sciences, Moscow, Russia.
authors.forename: Ludmila
authors.initials: L
authors.lastname: Kornilova
authors.affiliation: Université libre de Bruxelles &Erasmus Hospital, Department of Cardiology, Laboratory of Physics and Physiology, Brussels, Belgium.
authors.forename: Quentin
authors.initials: Q
authors.lastname: Delière
authors.affiliation: StatUa center for statistics, University of Antwerp, Antwerp, Belgium.
authors.forename: Erik
authors.initials: E
authors.lastname: Fransen
authors.affiliation: Laboratory of Vestibular Physiology, Institute of Biomedical Problems of the Russian academy of sciences, Moscow, Russia.
authors.forename: Dmitrii
authors.initials: D
authors.lastname: Glukhikh
authors.affiliation: Human Aerospace Laboratory, Icahn School of Medicine at Mount Sinai, New York City, USA.
authors.forename: Steven T
authors.initials: ST
authors.lastname: Moore
authors.affiliation: Lyon Neuroscience Research Center, IMPACT Team, University of Lyon, France.
authors.forename: Gilles
authors.initials: G
authors.lastname: Clément
authors.affiliation: Autonomic Dysfunction Center, Vanderbilt University School of Medicine, Nashville, USA.
authors.forename: André
authors.initials: A
authors.lastname: Diedrich
authors.affiliation: Sydney Human Factors Research, School of Psychology, University of Sydney, Australia.
authors.forename: Hamish
authors.initials: H
authors.lastname: MacDougall
authors.affiliation: Antwerp University Research center for Equilibrium and Aerospace, Dept. of Biomedical Physics, University of Antwerp, Belgium.
authors.forename: Floris L
authors.initials: FL
authors.lastname: Wuyts
mesh_terms: D000328:Adult; D018480:Astronauts; D001794:Blood Pressure; D002319:Cardiovascular System / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011187:Posture; D013026:Space Flight; D014722:Vestibule, Labyrinth / Q000503:physiopathology*; D014785:Vision, Ocular / Q000502:physiology