Evidence for prejunctional and postjunctional antagonism of the sympathetic neuroeffector junction by acetylcholine in canine cardiac Purkinje fibers

R. F. Gilmour, D. P. Zipes

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

This study determined whether acetylcholine inhibited changes in action potential duration and developed tension in canine Purkinje fibers produced by norepinephrine released during field stimulation more than it inhibited changes produced by superfusion with norepinephrine. Field stimulation increased action potential duration measured at 75% of repolarization by 9.6 ms and increased active tension by 35.5%. Acetylcholine (10-6 M) almost completely inhibited changes in action potential duration and developed tension during field stimulation. Norepinephrine (10-8 M to 5 x 10-8 M) superfusion during normal pacing increased developed tension by 40.6%. Acetylcholine (10-6 M) reduced this increase to 19.7%. Thus, acetylcholine inhibited the increase in tension during field stimulation by 90.7%, whereas it inhibited equivalent increases in tension produced by superfusion with norepinephrine by only 51.4% (p < 0.01). These data suggest that acetylcholine antagonizes the effects of adrenergic stimulation by pre- and postjunctional inhibitory actions in canine cardiac Purkinje fibers.

Original languageEnglish
Pages (from-to)760-765
Number of pages6
JournalJournal of the American College of Cardiology
Volume3
Issue number3
StatePublished - 1984

Fingerprint

Neuroeffector Junction
Purkinje Fibers
Acetylcholine
Canidae
Norepinephrine
Action Potentials
Adrenergic Agents

ASJC Scopus subject areas

  • Nursing(all)

Cite this

@article{94a6d8ed3ed546f8af4700d50b045456,
title = "Evidence for prejunctional and postjunctional antagonism of the sympathetic neuroeffector junction by acetylcholine in canine cardiac Purkinje fibers",
abstract = "This study determined whether acetylcholine inhibited changes in action potential duration and developed tension in canine Purkinje fibers produced by norepinephrine released during field stimulation more than it inhibited changes produced by superfusion with norepinephrine. Field stimulation increased action potential duration measured at 75{\%} of repolarization by 9.6 ms and increased active tension by 35.5{\%}. Acetylcholine (10-6 M) almost completely inhibited changes in action potential duration and developed tension during field stimulation. Norepinephrine (10-8 M to 5 x 10-8 M) superfusion during normal pacing increased developed tension by 40.6{\%}. Acetylcholine (10-6 M) reduced this increase to 19.7{\%}. Thus, acetylcholine inhibited the increase in tension during field stimulation by 90.7{\%}, whereas it inhibited equivalent increases in tension produced by superfusion with norepinephrine by only 51.4{\%} (p < 0.01). These data suggest that acetylcholine antagonizes the effects of adrenergic stimulation by pre- and postjunctional inhibitory actions in canine cardiac Purkinje fibers.",
author = "Gilmour, {R. F.} and Zipes, {D. P.}",
year = "1984",
language = "English",
volume = "3",
pages = "760--765",
journal = "Journal of the American College of Cardiology",
issn = "0735-1097",
publisher = "Elsevier USA",
number = "3",

}

TY - JOUR

T1 - Evidence for prejunctional and postjunctional antagonism of the sympathetic neuroeffector junction by acetylcholine in canine cardiac Purkinje fibers

AU - Gilmour, R. F.

AU - Zipes, D. P.

PY - 1984

Y1 - 1984

N2 - This study determined whether acetylcholine inhibited changes in action potential duration and developed tension in canine Purkinje fibers produced by norepinephrine released during field stimulation more than it inhibited changes produced by superfusion with norepinephrine. Field stimulation increased action potential duration measured at 75% of repolarization by 9.6 ms and increased active tension by 35.5%. Acetylcholine (10-6 M) almost completely inhibited changes in action potential duration and developed tension during field stimulation. Norepinephrine (10-8 M to 5 x 10-8 M) superfusion during normal pacing increased developed tension by 40.6%. Acetylcholine (10-6 M) reduced this increase to 19.7%. Thus, acetylcholine inhibited the increase in tension during field stimulation by 90.7%, whereas it inhibited equivalent increases in tension produced by superfusion with norepinephrine by only 51.4% (p < 0.01). These data suggest that acetylcholine antagonizes the effects of adrenergic stimulation by pre- and postjunctional inhibitory actions in canine cardiac Purkinje fibers.

AB - This study determined whether acetylcholine inhibited changes in action potential duration and developed tension in canine Purkinje fibers produced by norepinephrine released during field stimulation more than it inhibited changes produced by superfusion with norepinephrine. Field stimulation increased action potential duration measured at 75% of repolarization by 9.6 ms and increased active tension by 35.5%. Acetylcholine (10-6 M) almost completely inhibited changes in action potential duration and developed tension during field stimulation. Norepinephrine (10-8 M to 5 x 10-8 M) superfusion during normal pacing increased developed tension by 40.6%. Acetylcholine (10-6 M) reduced this increase to 19.7%. Thus, acetylcholine inhibited the increase in tension during field stimulation by 90.7%, whereas it inhibited equivalent increases in tension produced by superfusion with norepinephrine by only 51.4% (p < 0.01). These data suggest that acetylcholine antagonizes the effects of adrenergic stimulation by pre- and postjunctional inhibitory actions in canine cardiac Purkinje fibers.

UR - http://www.scopus.com/inward/record.url?scp=0021332125&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0021332125&partnerID=8YFLogxK

M3 - Article

C2 - 6141196

AN - SCOPUS:0021332125

VL - 3

SP - 760

EP - 765

JO - Journal of the American College of Cardiology

JF - Journal of the American College of Cardiology

SN - 0735-1097

IS - 3

ER -