Atrial distension, arterial pulsation, and vasopressin release during negative pressure breathing in humans

TY - JOUR

T1 - Atrial distension, arterial pulsation, and vasopressin release during negative pressure breathing in humans

AU - Pump, B

AU - Damgaard, M

AU - Gabrielsen, A

AU - Bie, P

AU - Christensen, N J

AU - Norsk, P

PY - 2001/10/1

Y1 - 2001/10/1

N2 - During an antiorthostatic posture change, left atrial (LA) diameter and arterial pulse pressure (PP) increase, and plasma arginine vasopressin (AVP) is suppressed. By comparing the effects of a 15-min posture change from seated to supine with those of 15-min seated negative pressure breathing in eight healthy males, we tested the hypothesis that with similar increases in LA diameter, suppression of AVP release is dependent on the degree of increase in PP. LA diameter increased similarly during the posture change and negative pressure breathing (-9 to -24 mmHg) from between 30 and 31 +/- 1 to 34 +/- 1 mm (P <0.05). The increase in PP from 38 +/- 2 to 44 +/- 2 mmHg (P <0.05) was sustained during the posture change but only increased during the initial 5 min of negative pressure breathing from 36 +/- 3 to 42 +/- 3 mmHg (P <0.05). Aortic transmural pressure decreased during the posture change and increased during negative pressure breathing. Plasma AVP was suppressed to a lower value during the posture change (from 1.5 +/- 0.3 to 1.2 +/- 0.2 pg/ml, P <0.05) than during negative pressure breathing (from 1.5 +/- 0.3 to 1.4 +/- 0.3 pg/ml). Plasma norepinephrine was decreased similarly during the posture change and negative pressure breathing compared with seated control. In conclusion, the results are in compliance with the hypothesis that during maneuvers with similar cardiac distension, suppression of AVP release is dependent on the increase in PP and, furthermore, probably unaffected by static aortic baroreceptor stimulation.

AB - During an antiorthostatic posture change, left atrial (LA) diameter and arterial pulse pressure (PP) increase, and plasma arginine vasopressin (AVP) is suppressed. By comparing the effects of a 15-min posture change from seated to supine with those of 15-min seated negative pressure breathing in eight healthy males, we tested the hypothesis that with similar increases in LA diameter, suppression of AVP release is dependent on the degree of increase in PP. LA diameter increased similarly during the posture change and negative pressure breathing (-9 to -24 mmHg) from between 30 and 31 +/- 1 to 34 +/- 1 mm (P <0.05). The increase in PP from 38 +/- 2 to 44 +/- 2 mmHg (P <0.05) was sustained during the posture change but only increased during the initial 5 min of negative pressure breathing from 36 +/- 3 to 42 +/- 3 mmHg (P <0.05). Aortic transmural pressure decreased during the posture change and increased during negative pressure breathing. Plasma AVP was suppressed to a lower value during the posture change (from 1.5 +/- 0.3 to 1.2 +/- 0.2 pg/ml, P <0.05) than during negative pressure breathing (from 1.5 +/- 0.3 to 1.4 +/- 0.3 pg/ml). Plasma norepinephrine was decreased similarly during the posture change and negative pressure breathing compared with seated control. In conclusion, the results are in compliance with the hypothesis that during maneuvers with similar cardiac distension, suppression of AVP release is dependent on the increase in PP and, furthermore, probably unaffected by static aortic baroreceptor stimulation.

KW - Adult

KW - Arginine Vasopressin

KW - Arteries

KW - Atrial Function

KW - Humans

KW - Male

KW - Norepinephrine

KW - Posture

KW - Pulse

KW - Respiratory Physiological Phenomena

KW - Vasopressins

KW - Ventilators, Negative-Pressure

M3 - Journal article

C2 - 11557547

SN - 0363-6135

VL - 281

SP - H1583-8

JO - American Journal of Physiology - Heart and Circulatory Physiology

JF - American Journal of Physiology - Heart and Circulatory Physiology

IS - 4

ER -