title: Responses of plasma human atrial natriuretic factor to high intensity submaximal exercise in the heat.
abstract: No data exists regarding responses of human atrial natriuretic factor (ANF) to exercise in the heat. The purpose of this study was to examine the responses of plasma ANF to high intensity submaximal (71% +/- 0.9 VO2max) exercise in the heat over an eight day acclimation period. Fourteen healthy males volunteered to participate in the study. Subjects performed intermittent exercises on a treadmill (0% grade) during 50 min of each 100 min trial in an environmental chamber maintained at 41.2 +/- 0.5 degrees C, 39.0 +/- 1.7% relative humidity. Blood was obtained from an antecubital vein after standing 20 min in the heat prior to exercise, and immediately after exercise. Measures were compared on days 1, 4 and 8. ANF did not change pre- to post-exercise nor did it change over the eight day heat acclimation period despite other heat acclimation adaptations. Conversely, plasma aldosterone (ALDO), renin activity (PRA) and cortisol (COR) all increased (p less than 0.05) pre- to post-exercise on each day but again no changes were observed over the eight day period. These data support that ANF may not increase when ALDO and PRA increases are observed.
authors.affiliation: Exercise Physiology Division, US Army Research Institute of Environmental Medicine, Natick, MA 01760-5007.
authors.forename: W J
authors.initials: WJ
authors.lastname: Kraemer
authors.forename: L E
authors.initials: LE
authors.lastname: Armstrong
authors.forename: R W
authors.initials: RW
authors.lastname: Hubbard
authors.forename: L J
authors.initials: LJ
authors.lastname: Marchitelli
authors.forename: N
authors.initials: N
authors.lastname: Leva
authors.forename: P B
authors.initials: PB
authors.lastname: Rock
authors.forename: J E
authors.initials: JE
authors.lastname: Dziados
mesh_terms: D000064:Acclimatization; D000328:Adult; D000450:Aldosterone / Q000097:blood; D009320:Atrial Natriuretic Factor / Q000097:blood*; D006358:Hot Temperature; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D005082:Physical Exertion; D011188:Potassium / Q000097:blood; D012083:Renin / Q000097:blood; D012964:Sodium / Q000097:blood; D013997:Time Factors
chemical_list: C472955:NPPA protein, human; D000450:Aldosterone; D009320:Atrial Natriuretic Factor; D012964:Sodium; D012083:Renin; D011188:Potassium; D006854:Hydrocortisone