Neural and local effects of hypoxia on cardiovascular responses to obstructive apnea

Hartmut Schneider, C. D. Schaub, C. A. Chen, K. A. Andreoni, Alan R Schwartz, Philip L Smith, J. L. Robotham, C. P. O'Donnell

Research output: Contribution to journalArticle

Abstract

Obstructive sleep apnea (OSA) acutely increases systemic (Psa) and pulmonary (Ppa) arterial pressures and decreases ventricular stroke volume (SV). In this study, we used a canine model of OSA (n = 6) to examine the role of hypoxia and the autonomic nervous system (ANS) in mediating these cardiovascular responses. Hyperoxia (40% oxygen) completely blocked any increase in Ppa in response to obstructive apnea but only attenuated the increase in Psa. In contrast, after blockade of the ANS (20 mg/kg iv hexamethonium), obstructive apnea produced a decrease in Psa (-5.9 mmHg; P <0.05) but no change in Ppa, and the fall in SV was abolished. Both the fall in Psa and the rise in Ppa that persisted after ANS blockade were abolished when apneas were induced during hyperoxia. We conclude that 1) hypoxia can account for all of the Ppa and the majority of the Psa response to obstructive apnea, 2) the ANS increases Psa but not Ppa in obstructive apnea, 3) the local effects of hypoxia associated with obstructive apnea cause vasodilation in the systemic vasculature and vasoconstriction in the pulmonary vasculature, and 4) a rise in Psa acts as an afterload to the heart and decreases SV over the course of the apnea.

Original languageEnglish (US)
Pages (from-to)1093-1102
Number of pages10
JournalJournal of Applied Physiology
Volume88
Issue number3
StatePublished - Mar 2000

Fingerprint

Apnea
Autonomic Nervous System
Lung
Stroke Volume
Hyperoxia
Obstructive Sleep Apnea
Hexamethonium
Hypoxia
Vasoconstriction
Vasodilation
Canidae
Arterial Pressure
Oxygen

Keywords

  • Autonomic nervous system
  • Canine
  • Hyperoxia
  • Pulmonary arterial pressure
  • Sleep
  • Systemic arterial pressure
  • Ventricular stroke volume

ASJC Scopus subject areas

  • Physiology
  • Endocrinology
  • Orthopedics and Sports Medicine
  • Physical Therapy, Sports Therapy and Rehabilitation

Cite this

Schneider, H., Schaub, C. D., Chen, C. A., Andreoni, K. A., Schwartz, A. R., Smith, P. L., ... O'Donnell, C. P. (2000). Neural and local effects of hypoxia on cardiovascular responses to obstructive apnea. Journal of Applied Physiology, 88(3), 1093-1102.

Neural and local effects of hypoxia on cardiovascular responses to obstructive apnea. / Schneider, Hartmut; Schaub, C. D.; Chen, C. A.; Andreoni, K. A.; Schwartz, Alan R; Smith, Philip L; Robotham, J. L.; O'Donnell, C. P.

In: Journal of Applied Physiology, Vol. 88, No. 3, 03.2000, p. 1093-1102.

Research output: Contribution to journalArticle

Schneider, H, Schaub, CD, Chen, CA, Andreoni, KA, Schwartz, AR, Smith, PL, Robotham, JL & O'Donnell, CP 2000, 'Neural and local effects of hypoxia on cardiovascular responses to obstructive apnea', Journal of Applied Physiology, vol. 88, no. 3, pp. 1093-1102.
Schneider H, Schaub CD, Chen CA, Andreoni KA, Schwartz AR, Smith PL et al. Neural and local effects of hypoxia on cardiovascular responses to obstructive apnea. Journal of Applied Physiology. 2000 Mar;88(3):1093-1102.
Schneider, Hartmut ; Schaub, C. D. ; Chen, C. A. ; Andreoni, K. A. ; Schwartz, Alan R ; Smith, Philip L ; Robotham, J. L. ; O'Donnell, C. P. / Neural and local effects of hypoxia on cardiovascular responses to obstructive apnea. In: Journal of Applied Physiology. 2000 ; Vol. 88, No. 3. pp. 1093-1102.
@article{83da6ac249144ddf8ffe445469b0ef6d,
title = "Neural and local effects of hypoxia on cardiovascular responses to obstructive apnea",
abstract = "Obstructive sleep apnea (OSA) acutely increases systemic (Psa) and pulmonary (Ppa) arterial pressures and decreases ventricular stroke volume (SV). In this study, we used a canine model of OSA (n = 6) to examine the role of hypoxia and the autonomic nervous system (ANS) in mediating these cardiovascular responses. Hyperoxia (40{\%} oxygen) completely blocked any increase in Ppa in response to obstructive apnea but only attenuated the increase in Psa. In contrast, after blockade of the ANS (20 mg/kg iv hexamethonium), obstructive apnea produced a decrease in Psa (-5.9 mmHg; P <0.05) but no change in Ppa, and the fall in SV was abolished. Both the fall in Psa and the rise in Ppa that persisted after ANS blockade were abolished when apneas were induced during hyperoxia. We conclude that 1) hypoxia can account for all of the Ppa and the majority of the Psa response to obstructive apnea, 2) the ANS increases Psa but not Ppa in obstructive apnea, 3) the local effects of hypoxia associated with obstructive apnea cause vasodilation in the systemic vasculature and vasoconstriction in the pulmonary vasculature, and 4) a rise in Psa acts as an afterload to the heart and decreases SV over the course of the apnea.",
keywords = "Autonomic nervous system, Canine, Hyperoxia, Pulmonary arterial pressure, Sleep, Systemic arterial pressure, Ventricular stroke volume",
author = "Hartmut Schneider and Schaub, {C. D.} and Chen, {C. A.} and Andreoni, {K. A.} and Schwartz, {Alan R} and Smith, {Philip L} and Robotham, {J. L.} and O'Donnell, {C. P.}",
year = "2000",
month = "3",
language = "English (US)",
volume = "88",
pages = "1093--1102",
journal = "Journal of Applied Physiology",
issn = "0161-7567",
publisher = "American Physiological Society",
number = "3",

}

TY - JOUR

T1 - Neural and local effects of hypoxia on cardiovascular responses to obstructive apnea

AU - Schneider, Hartmut

AU - Schaub, C. D.

AU - Chen, C. A.

AU - Andreoni, K. A.

AU - Schwartz, Alan R

AU - Smith, Philip L

AU - Robotham, J. L.

AU - O'Donnell, C. P.

PY - 2000/3

Y1 - 2000/3

N2 - Obstructive sleep apnea (OSA) acutely increases systemic (Psa) and pulmonary (Ppa) arterial pressures and decreases ventricular stroke volume (SV). In this study, we used a canine model of OSA (n = 6) to examine the role of hypoxia and the autonomic nervous system (ANS) in mediating these cardiovascular responses. Hyperoxia (40% oxygen) completely blocked any increase in Ppa in response to obstructive apnea but only attenuated the increase in Psa. In contrast, after blockade of the ANS (20 mg/kg iv hexamethonium), obstructive apnea produced a decrease in Psa (-5.9 mmHg; P <0.05) but no change in Ppa, and the fall in SV was abolished. Both the fall in Psa and the rise in Ppa that persisted after ANS blockade were abolished when apneas were induced during hyperoxia. We conclude that 1) hypoxia can account for all of the Ppa and the majority of the Psa response to obstructive apnea, 2) the ANS increases Psa but not Ppa in obstructive apnea, 3) the local effects of hypoxia associated with obstructive apnea cause vasodilation in the systemic vasculature and vasoconstriction in the pulmonary vasculature, and 4) a rise in Psa acts as an afterload to the heart and decreases SV over the course of the apnea.

AB - Obstructive sleep apnea (OSA) acutely increases systemic (Psa) and pulmonary (Ppa) arterial pressures and decreases ventricular stroke volume (SV). In this study, we used a canine model of OSA (n = 6) to examine the role of hypoxia and the autonomic nervous system (ANS) in mediating these cardiovascular responses. Hyperoxia (40% oxygen) completely blocked any increase in Ppa in response to obstructive apnea but only attenuated the increase in Psa. In contrast, after blockade of the ANS (20 mg/kg iv hexamethonium), obstructive apnea produced a decrease in Psa (-5.9 mmHg; P <0.05) but no change in Ppa, and the fall in SV was abolished. Both the fall in Psa and the rise in Ppa that persisted after ANS blockade were abolished when apneas were induced during hyperoxia. We conclude that 1) hypoxia can account for all of the Ppa and the majority of the Psa response to obstructive apnea, 2) the ANS increases Psa but not Ppa in obstructive apnea, 3) the local effects of hypoxia associated with obstructive apnea cause vasodilation in the systemic vasculature and vasoconstriction in the pulmonary vasculature, and 4) a rise in Psa acts as an afterload to the heart and decreases SV over the course of the apnea.

KW - Autonomic nervous system

KW - Canine

KW - Hyperoxia

KW - Pulmonary arterial pressure

KW - Sleep

KW - Systemic arterial pressure

KW - Ventricular stroke volume

UR - http://www.scopus.com/inward/record.url?scp=0034058705&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0034058705&partnerID=8YFLogxK

M3 - Article

VL - 88

SP - 1093

EP - 1102

JO - Journal of Applied Physiology

JF - Journal of Applied Physiology

SN - 0161-7567

IS - 3

ER -