title: Neural autonomic control in orthostatic intolerance.
abstract: Inability to maintain the upright position is manifested by a number of symptoms shared by either human pathophysiology and conditions following weightlessness or bed rest. Alterations of the neural sympathetic cardiovascular control have been suggested to be one of the potential underlying etiopathogenetic mechanisms in these conditions. We hypothesize that the study of the autonomic profile of human orthostatic intolerance syndromes may furnish a valuable insight into the complexity of the sympathetic alterations leading to a reduced gravitational tolerance. In the present paper we describe abnormalities both in the magnitude and in the pattern of the sympathetic neural firing observed in patients affected by orthostatic intolerance, attending the upright position. Also, we discuss similarity and differences in the neural sympathetic mechanisms regulating the cardiovascular system during the gravitational stimulus both in clinical syndromes and in subjects returning from space.
authors.affiliation: Internal Medicine "Bolognini" Hospital, Seriate, Bergamo, Italy. raffaello.furlan@unimi.it
authors.forename: Raffaello
authors.initials: R
authors.lastname: Furlan
authors.forename: Franca
authors.initials: F
authors.lastname: Barbic
authors.forename: Francesco
authors.initials: F
authors.lastname: Casella
authors.forename: Giorgio
authors.initials: G
authors.lastname: Severgnini
authors.forename: Luca
authors.initials: L
authors.lastname: Zenoni
authors.forename: Angelo
authors.initials: A
authors.lastname: Mercieri
authors.forename: Ruggero
authors.initials: R
authors.lastname: Mangili
authors.forename: Giorgio
authors.initials: G
authors.lastname: Costantino
authors.forename: Alberto
authors.initials: A
authors.lastname: Porta
mesh_terms: D000200:Action Potentials / Q000502:physiology; D001341:Autonomic Nervous System / Q000503:physiopathology*; D001794:Blood Pressure; D006112:Gravitation; D006801:Humans; D009474:Neurons / Q000502:physiology*; D009638:Norepinephrine / Q000097:blood; D054971:Orthostatic Intolerance / Q000097:blood / Q000473:pathology / Q000503:physiopathology*; D011187:Posture; D013057:Spectrum Analysis / Q000379:methods; D014893:Weightlessness
chemical_list: D009638:Norepinephrine