title: The role of posture on the changes in plasma atrial natriuretic factor and arginine vasopressin levels during immersion.
abstract: In seven healthy male volunteers we investigated changes in plasma atrial natriuretic factor [( ANF]), arginine vasopressin [( AVP]) and plasma volume (PV) during supine immersion. Twenty minutes head-out water immersion in a supine position in a thermo-neutral water bath attenuated the increase in PV induced by 20 min in a supine position in air, but increased the mean plasma [ANF] from 32.0 pg.ml-1, SEM 5.1 to 53.3 pg.ml-1, SEM 3.6 and decreased the mean plasma [AVP] from 1.4 pg.ml-1, SEM 0.1 to 0.9 pg.ml-1, SEM 0.04. Simultaneously, diuresis and natriuresis increased markedly. During a 20-min control period in the supine posture without immersion, PV, plasma [ANF] and [AVP] remained unaffected while diuresis and natriuresis did not increase to the same extent. These data suggest that an increase in the central blood volume induced by a weak external hydrostatic pressure during supine immersion triggered the changes in plasma [ANF] and [AVP] and that the increase was probably due to a shift of blood volume from peripheral to central vessels. The changes in plasma [ANF] contributed to the changes in natriuresis.
authors: Laboratoire de Physiologie, Faculté de Médecine, Besançon, France.
authors: J P
authors: JP
authors: Wolf
authors: N U
authors: NU
authors: Nguyen
authors: A
authors: A
authors: Baulay
authors: G
authors: G
authors: Dumoulin
authors: S
authors: S
authors: Berthelay
mesh_terms: D000328:Adult; D001127:Arginine Vasopressin / Q000097:blood*; D009320:Atrial Natriuretic Factor / Q000097:blood*; D001794:Blood Pressure; D001798:Blood Proteins / Q000378:metabolism; D001810:Blood Volume; D004231:Diuresis; D006339:Heart Rate; D006801:Humans; D007101:Immersion; D008297:Male; D009318:Natriuresis; D009994:Osmolar Concentration; D011187:Posture; D012709:Serum Albumin / Q000378:metabolism; D012964:Sodium / Q000097:blood
chemical_list: D001798:Blood Proteins; D012709:Serum Albumin; D001127:Arginine Vasopressin; D009320:Atrial Natriuretic Factor; D012964:Sodium