α2-adrenergic modulation of colonic tone during hyperventilation

Adil Eddie Bharucha, Vera Novak, Michael Camilleri, Alan R. Zinsmeister, Russell B. Hanson, Phillip Anson Low

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Our aims were to assess the role of adrenergic modulation in the hyperventilation-induced increase in colonic tone. Of 40 healthy volunteers, 12 received placebo (saline) and the remaining 28 received either clonidine, yohimbine, phenylephrine, or ritodrine. Time-frequency mapping of heart rate based on Wigner distribution assessed variations in parasympathetic and sympathetic activity during hyperventilation. Tone in the descending colon was recorded by a barostat balloon before, during, and after 5 min of hyperventilation. Heart rate spectral analysis suggested diminished sympathetic and vagal activity during hyperventilation and increased sympathetic and vagal activity after hyperventilation. Adrenergic agents influenced (P = 0.01) the tonic response after, but not during, hyperventilation. Yohimbine reduced the increment in colonic tone after hyperventilation compared with saline (P < 0.05) and clonidine (P = 0.002); phenylephrine and ritodrine had no effects. Different mechanisms modulate the increase in colonic tone during and after hyperventilation. Yohimbine attenuates the increase in colonic tone after hyperventilation probably by enhancing inhibitory sympathetic input to the colon.

Original languageEnglish (US)
JournalAmerican Journal of Physiology - Gastrointestinal and Liver Physiology
Volume273
Issue number5 36-5
StatePublished - 1997

Fingerprint

Hyperventilation
Adrenergic Agents
Yohimbine
Ritodrine
Clonidine
Phenylephrine
Heart Rate
Descending Colon
Healthy Volunteers
Colon
Placebos

Keywords

  • Spectral analysis of heart rate

ASJC Scopus subject areas

  • Gastroenterology
  • Physiology
  • Physiology (medical)

Cite this

α2-adrenergic modulation of colonic tone during hyperventilation. / Bharucha, Adil Eddie; Novak, Vera; Camilleri, Michael; Zinsmeister, Alan R.; Hanson, Russell B.; Low, Phillip Anson.

In: American Journal of Physiology - Gastrointestinal and Liver Physiology, Vol. 273, No. 5 36-5, 1997.

Research output: Contribution to journalArticle

@article{ff2e6a15c5064d7a8c6928197eca6779,
title = "α2-adrenergic modulation of colonic tone during hyperventilation",
abstract = "Our aims were to assess the role of adrenergic modulation in the hyperventilation-induced increase in colonic tone. Of 40 healthy volunteers, 12 received placebo (saline) and the remaining 28 received either clonidine, yohimbine, phenylephrine, or ritodrine. Time-frequency mapping of heart rate based on Wigner distribution assessed variations in parasympathetic and sympathetic activity during hyperventilation. Tone in the descending colon was recorded by a barostat balloon before, during, and after 5 min of hyperventilation. Heart rate spectral analysis suggested diminished sympathetic and vagal activity during hyperventilation and increased sympathetic and vagal activity after hyperventilation. Adrenergic agents influenced (P = 0.01) the tonic response after, but not during, hyperventilation. Yohimbine reduced the increment in colonic tone after hyperventilation compared with saline (P < 0.05) and clonidine (P = 0.002); phenylephrine and ritodrine had no effects. Different mechanisms modulate the increase in colonic tone during and after hyperventilation. Yohimbine attenuates the increase in colonic tone after hyperventilation probably by enhancing inhibitory sympathetic input to the colon.",
keywords = "Spectral analysis of heart rate",
author = "Bharucha, {Adil Eddie} and Vera Novak and Michael Camilleri and Zinsmeister, {Alan R.} and Hanson, {Russell B.} and Low, {Phillip Anson}",
year = "1997",
language = "English (US)",
volume = "273",
journal = "American Journal of Physiology - Renal Fluid and Electrolyte Physiology",
issn = "1931-857X",
publisher = "American Physiological Society",
number = "5 36-5",

}

TY - JOUR

T1 - α2-adrenergic modulation of colonic tone during hyperventilation

AU - Bharucha, Adil Eddie

AU - Novak, Vera

AU - Camilleri, Michael

AU - Zinsmeister, Alan R.

AU - Hanson, Russell B.

AU - Low, Phillip Anson

PY - 1997

Y1 - 1997

N2 - Our aims were to assess the role of adrenergic modulation in the hyperventilation-induced increase in colonic tone. Of 40 healthy volunteers, 12 received placebo (saline) and the remaining 28 received either clonidine, yohimbine, phenylephrine, or ritodrine. Time-frequency mapping of heart rate based on Wigner distribution assessed variations in parasympathetic and sympathetic activity during hyperventilation. Tone in the descending colon was recorded by a barostat balloon before, during, and after 5 min of hyperventilation. Heart rate spectral analysis suggested diminished sympathetic and vagal activity during hyperventilation and increased sympathetic and vagal activity after hyperventilation. Adrenergic agents influenced (P = 0.01) the tonic response after, but not during, hyperventilation. Yohimbine reduced the increment in colonic tone after hyperventilation compared with saline (P < 0.05) and clonidine (P = 0.002); phenylephrine and ritodrine had no effects. Different mechanisms modulate the increase in colonic tone during and after hyperventilation. Yohimbine attenuates the increase in colonic tone after hyperventilation probably by enhancing inhibitory sympathetic input to the colon.

AB - Our aims were to assess the role of adrenergic modulation in the hyperventilation-induced increase in colonic tone. Of 40 healthy volunteers, 12 received placebo (saline) and the remaining 28 received either clonidine, yohimbine, phenylephrine, or ritodrine. Time-frequency mapping of heart rate based on Wigner distribution assessed variations in parasympathetic and sympathetic activity during hyperventilation. Tone in the descending colon was recorded by a barostat balloon before, during, and after 5 min of hyperventilation. Heart rate spectral analysis suggested diminished sympathetic and vagal activity during hyperventilation and increased sympathetic and vagal activity after hyperventilation. Adrenergic agents influenced (P = 0.01) the tonic response after, but not during, hyperventilation. Yohimbine reduced the increment in colonic tone after hyperventilation compared with saline (P < 0.05) and clonidine (P = 0.002); phenylephrine and ritodrine had no effects. Different mechanisms modulate the increase in colonic tone during and after hyperventilation. Yohimbine attenuates the increase in colonic tone after hyperventilation probably by enhancing inhibitory sympathetic input to the colon.

KW - Spectral analysis of heart rate

UR - http://www.scopus.com/inward/record.url?scp=0030714650&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030714650&partnerID=8YFLogxK

M3 - Article

C2 - 9374712

AN - SCOPUS:0030714650

VL - 273

JO - American Journal of Physiology - Renal Fluid and Electrolyte Physiology

JF - American Journal of Physiology - Renal Fluid and Electrolyte Physiology

SN - 1931-857X

IS - 5 36-5

ER -