title: Endocrine status and LBNP-induced hormone changes during a 438-day spaceflight: a case study.
abstract: We investigated basal levels and lower body negative pressure (LBNP)-induced changes of volume regulating (PRA, aldosterone, AVP, ANP99-126) and other stress-sensitive hormones (catecholamines, cortisol, ACTH) in venous plasma from one cosmonaut before (-45 d), during (3, 170, 287, 430 d) and after (+4, +90 d) a record-breaking long-term (438 d) spaceflight. Blood was taken at the beginning and immediately after ending LBNP (-15/-30/-35 mm Hg for 15/15/10 min, respectively) preflight supine, inflight, and postflight supine. PRA, aldosterone, and vasopressin levels stayed within normal boundaries during the entire flight and after landing. Catecholamines exceeded reference limits (epinephrine > 140 pg x ml(-1), norepinephrine >1000 pg x ml(-1) 5 and 9 mo inflight, and 4 d postflight. ANP and cGMP were lower inflight (p<0.04) than pre- or postflight. Cortisol and ACTH were not consistently altered. LBNP-induced hormonal changes were not different (p>0.05) in microgravity and 1-G. Based on data from one cosmonaut, we conclude that long-term spaceflight up to 430 d duration appeared to lower plasma ANP and cGMP during flight and occasionally elevate catecholamine levels, without significantly altering LBNP-induced relative hormone changes as compared with those observed on the ground.
authors.affiliation: Austrian Society for Aerospace Medicine, Institute for Adaptational and Spaceflight Physiology, Graz.
authors.forename: H G
authors.initials: HG
authors.lastname: Hinghofer-Szalkay
authors.forename: V B
authors.initials: VB
authors.lastname: Noskov
authors.forename: A
authors.initials: A
authors.lastname: Rössler
authors.forename: A I
authors.initials: AI
authors.lastname: Grigoriev
authors.forename: R
authors.initials: R
authors.lastname: Kvetnansky
authors.forename: V V
authors.initials: VV
authors.lastname: Polyakow
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D000324:Adrenocorticotropic Hormone / Q000097:blood; D000450:Aldosterone / Q000097:blood; D009320:Atrial Natriuretic Factor / Q000097:blood; D002395:Catecholamines / Q000097:blood; D006152:Cyclic GMP / Q000097:blood; D004703:Endocrine System / Q000502:physiology*; D006706:Homeostasis / Q000502:physiology; D006728:Hormones / Q000097:blood*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008150:Lower Body Negative Pressure / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D012083:Renin / Q000097:blood; D013026:Space Flight; D013312:Stress, Physiological / Q000097:blood; D016683:Supine Position; D013997:Time Factors; D014667:Vasopressins / Q000097:blood
chemical_list: D002395:Catecholamines; D006728:Hormones; D014667:Vasopressins; D000450:Aldosterone; D009320:Atrial Natriuretic Factor; D000324:Adrenocorticotropic Hormone; D012083:Renin; D006152:Cyclic GMP; D006854:Hydrocortisone