Independent control of mucosal and total airway blood flow during hypoxemia

S. Elsasser, W. M. Long, H. J. Baier, Alejandro D. Chediak, Adam Wanner

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

In the larger airways, the blood circulation forms a subepithelial (mucosal) and outer (peribronchial) microvascular network. This raises the possibility that blood flow in these two networks is regulated independently. We used hypoxemia as a stimulus to induce changes in tracheal mucosal blood flow normalized for systemic arterial pressure (Q̇(tr n)) measured with an inert soluble gas technique and total bronchial blood flow (Q̇(br)) and normalized Q̇(br)(Q̇(brn)) measured with an electromagnetic flow probe in anesthetized sheep. Fifteen minutes of hypoxemia [PO2 40 ± 7 (SD) Torr] decreased mean Q̇(tr n) from 1.1 ± 0.4 to 0.8 ± 0.4 ml · min-1 · mmHg-1 · 102 (-27%; P < 0.05; n = 7) and increased mean Q̇(br n) from 12.1 ± 3.2 to 17.1 ± 5.4 ml · min-1 · mmHg-1 · 102 (+41%; P < 0.05; n = 6). The rise in Q̇(br) correlated with cardiac output (r = 0.68; P < 0.05). Phentolamine pretreatment (0.1 mg/kg iv) blunted the hypoxemia-related decrease of mean Q̇(tr n) (-8%; P = NS). Tyramine (2.5 mg) applied locally to the trachea decreased mean Q̇(tr n) significantly after 30 and 45 min by 31 and 19%, respectively (P < 0.05). 6-Hydroxydopamine (0.2 mg 4 times for 1 h locally applied) prevented the hypoxemia-induced as well as local tyramine-induced decrease in mean Q̇(tr n) (0 and 0%). We conclude that, during arterial hypoxemia, 1) an increase in total airway blood flow is associated with a decrease in airway mucosal blood flow, 2) total airway blood flow correlates with cardiac output, and 3) the decrease in Q̇(tr n) is at least partly mediated by local catecholamine release. These findings suggest an independent adrenergic regulation of airway mucosal blood flow.

Original languageEnglish
Pages (from-to)223-228
Number of pages6
JournalJournal of Applied Physiology
Volume71
Issue number1
StatePublished - Jan 1 1991

Fingerprint

Tyramine
Cardiac Output
Noble Gases
Blood Circulation
Phentolamine
Oxidopamine
Electromagnetic Phenomena
Microvessels
Hypoxia
Trachea
Adrenergic Agents
Catecholamines
Sheep
Arterial Pressure

Keywords

  • adrenergic nervous system
  • bronchial circulation
  • microcirculation
  • vasoconstriction

ASJC Scopus subject areas

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

Cite this

Independent control of mucosal and total airway blood flow during hypoxemia. / Elsasser, S.; Long, W. M.; Baier, H. J.; Chediak, Alejandro D.; Wanner, Adam.

In: Journal of Applied Physiology, Vol. 71, No. 1, 01.01.1991, p. 223-228.

Research output: Contribution to journalArticle

@article{c73bfcf962e44659bbeae3f002697ea7,
title = "Independent control of mucosal and total airway blood flow during hypoxemia",
abstract = "In the larger airways, the blood circulation forms a subepithelial (mucosal) and outer (peribronchial) microvascular network. This raises the possibility that blood flow in these two networks is regulated independently. We used hypoxemia as a stimulus to induce changes in tracheal mucosal blood flow normalized for systemic arterial pressure (Q̇(tr n)) measured with an inert soluble gas technique and total bronchial blood flow (Q̇(br)) and normalized Q̇(br)(Q̇(brn)) measured with an electromagnetic flow probe in anesthetized sheep. Fifteen minutes of hypoxemia [PO2 40 ± 7 (SD) Torr] decreased mean Q̇(tr n) from 1.1 ± 0.4 to 0.8 ± 0.4 ml · min-1 · mmHg-1 · 102 (-27{\%}; P < 0.05; n = 7) and increased mean Q̇(br n) from 12.1 ± 3.2 to 17.1 ± 5.4 ml · min-1 · mmHg-1 · 102 (+41{\%}; P < 0.05; n = 6). The rise in Q̇(br) correlated with cardiac output (r = 0.68; P < 0.05). Phentolamine pretreatment (0.1 mg/kg iv) blunted the hypoxemia-related decrease of mean Q̇(tr n) (-8{\%}; P = NS). Tyramine (2.5 mg) applied locally to the trachea decreased mean Q̇(tr n) significantly after 30 and 45 min by 31 and 19{\%}, respectively (P < 0.05). 6-Hydroxydopamine (0.2 mg 4 times for 1 h locally applied) prevented the hypoxemia-induced as well as local tyramine-induced decrease in mean Q̇(tr n) (0 and 0{\%}). We conclude that, during arterial hypoxemia, 1) an increase in total airway blood flow is associated with a decrease in airway mucosal blood flow, 2) total airway blood flow correlates with cardiac output, and 3) the decrease in Q̇(tr n) is at least partly mediated by local catecholamine release. These findings suggest an independent adrenergic regulation of airway mucosal blood flow.",
keywords = "adrenergic nervous system, bronchial circulation, microcirculation, vasoconstriction",
author = "S. Elsasser and Long, {W. M.} and Baier, {H. J.} and Chediak, {Alejandro D.} and Adam Wanner",
year = "1991",
month = "1",
day = "1",
language = "English",
volume = "71",
pages = "223--228",
journal = "Journal of Applied Physiology",
issn = "8750-7587",
publisher = "American Physiological Society",
number = "1",

}

TY - JOUR

T1 - Independent control of mucosal and total airway blood flow during hypoxemia

AU - Elsasser, S.

AU - Long, W. M.

AU - Baier, H. J.

AU - Chediak, Alejandro D.

AU - Wanner, Adam

PY - 1991/1/1

Y1 - 1991/1/1

N2 - In the larger airways, the blood circulation forms a subepithelial (mucosal) and outer (peribronchial) microvascular network. This raises the possibility that blood flow in these two networks is regulated independently. We used hypoxemia as a stimulus to induce changes in tracheal mucosal blood flow normalized for systemic arterial pressure (Q̇(tr n)) measured with an inert soluble gas technique and total bronchial blood flow (Q̇(br)) and normalized Q̇(br)(Q̇(brn)) measured with an electromagnetic flow probe in anesthetized sheep. Fifteen minutes of hypoxemia [PO2 40 ± 7 (SD) Torr] decreased mean Q̇(tr n) from 1.1 ± 0.4 to 0.8 ± 0.4 ml · min-1 · mmHg-1 · 102 (-27%; P < 0.05; n = 7) and increased mean Q̇(br n) from 12.1 ± 3.2 to 17.1 ± 5.4 ml · min-1 · mmHg-1 · 102 (+41%; P < 0.05; n = 6). The rise in Q̇(br) correlated with cardiac output (r = 0.68; P < 0.05). Phentolamine pretreatment (0.1 mg/kg iv) blunted the hypoxemia-related decrease of mean Q̇(tr n) (-8%; P = NS). Tyramine (2.5 mg) applied locally to the trachea decreased mean Q̇(tr n) significantly after 30 and 45 min by 31 and 19%, respectively (P < 0.05). 6-Hydroxydopamine (0.2 mg 4 times for 1 h locally applied) prevented the hypoxemia-induced as well as local tyramine-induced decrease in mean Q̇(tr n) (0 and 0%). We conclude that, during arterial hypoxemia, 1) an increase in total airway blood flow is associated with a decrease in airway mucosal blood flow, 2) total airway blood flow correlates with cardiac output, and 3) the decrease in Q̇(tr n) is at least partly mediated by local catecholamine release. These findings suggest an independent adrenergic regulation of airway mucosal blood flow.

AB - In the larger airways, the blood circulation forms a subepithelial (mucosal) and outer (peribronchial) microvascular network. This raises the possibility that blood flow in these two networks is regulated independently. We used hypoxemia as a stimulus to induce changes in tracheal mucosal blood flow normalized for systemic arterial pressure (Q̇(tr n)) measured with an inert soluble gas technique and total bronchial blood flow (Q̇(br)) and normalized Q̇(br)(Q̇(brn)) measured with an electromagnetic flow probe in anesthetized sheep. Fifteen minutes of hypoxemia [PO2 40 ± 7 (SD) Torr] decreased mean Q̇(tr n) from 1.1 ± 0.4 to 0.8 ± 0.4 ml · min-1 · mmHg-1 · 102 (-27%; P < 0.05; n = 7) and increased mean Q̇(br n) from 12.1 ± 3.2 to 17.1 ± 5.4 ml · min-1 · mmHg-1 · 102 (+41%; P < 0.05; n = 6). The rise in Q̇(br) correlated with cardiac output (r = 0.68; P < 0.05). Phentolamine pretreatment (0.1 mg/kg iv) blunted the hypoxemia-related decrease of mean Q̇(tr n) (-8%; P = NS). Tyramine (2.5 mg) applied locally to the trachea decreased mean Q̇(tr n) significantly after 30 and 45 min by 31 and 19%, respectively (P < 0.05). 6-Hydroxydopamine (0.2 mg 4 times for 1 h locally applied) prevented the hypoxemia-induced as well as local tyramine-induced decrease in mean Q̇(tr n) (0 and 0%). We conclude that, during arterial hypoxemia, 1) an increase in total airway blood flow is associated with a decrease in airway mucosal blood flow, 2) total airway blood flow correlates with cardiac output, and 3) the decrease in Q̇(tr n) is at least partly mediated by local catecholamine release. These findings suggest an independent adrenergic regulation of airway mucosal blood flow.

KW - adrenergic nervous system

KW - bronchial circulation

KW - microcirculation

KW - vasoconstriction

UR - http://www.scopus.com/inward/record.url?scp=0025884679&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0025884679&partnerID=8YFLogxK

M3 - Article

C2 - 1917746

AN - SCOPUS:0025884679

VL - 71

SP - 223

EP - 228

JO - Journal of Applied Physiology

JF - Journal of Applied Physiology

SN - 8750-7587

IS - 1

ER -