Changes in membrane characteristics of heart muscle during inhibition.

The Journal of general physiology ·Vol. 40 ·No. 1 ·1956-09-20 ·Pages 135-45

EDWARDS C, KUFFLER SW, TRAUTWEIN W

Abstract

Membrane characteristics were studied in isolated muscle strands from auricles of frogs using the "square pulse" technique. Changes in the time course and spatial spread of subthreshold electrotonic potentials were measured. If acetylcholine is applied in concentrations which cause slowing or stoppage of the heart beat, the following changes are produced: (a) the length constant (lambda) of the membrane is reduced, (b) the time constant is shortened. The effects are reversible and increase with acetylcholine concentration. The membrane changes caused by acetylcholine dimmish with time. It is concluded that during acetylcholine inhibition, as well as during vagal inhibition, the conductance of the muscle membrane is increased. Appreciable changes in the resting membrane potential need not accompany inhibition.

Keywords

ACETYLCHOLINE/effects HEART/effect of drugs on

MeSH Terms

Acetylcholine/pharmacology Action Potentials Heart/drug effects Heart Rate Membrane Potentials Muscles Myocardium

Chemicals

Acetylcholine

Authors & Affiliations

3 authors, click to expand affiliations / ORCID

EDWARDS C

KUFFLER S W

TRAUTWEIN W

References (13)

13 references, click to expand

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Article Info

Journal

The Journal of general physiology

Abbr.

J Gen Physiol

ISSN

0022-1295

DOI

10.1085/jgp.40.1.135

Published

1956-09-20

Pages

135-45

Language

English

Region

United States

NLM ID

2985110R

PMCID

PMC2147603

Subset

External Links

PubMed source DOI: 10.1085/jgp.40.1.135 PMC Full Text View journal details

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