Document Detail


The effect of harmaline on force of contraction of the rat isolated atrium.
MedLine Citation:
PMID:  1122934     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
In rat isolated right atria, beating spontaneously at 30 degrees C, harmaline 8.3 times 10-5 M slowed atrial rate and enhanced force of contraction. The velocity of development of tension (dT/dt) increased and time to peak tension was lengthened. Electrical drive of otherwise quiescent left atria showed that (1) within the range of change of rate induced by harmaline the reduction of frequency of stimulation increased dT/dt and peak tension developed, and (2) at a constant rate of stimulation harmaline produced a prolongation of time to peak tension and an enhancement of peak tension. We concluded that two mechanisms are responsible for the inotropic action of harmaline on rat atrium: (1) an increase in dT/dt due to the lengthening of the interval between beats; (2) a direct action of harmaline on the processes responsible for atrial contraction, which determines a lengthening of time to peak tension.
Authors:
H Chamorro; J Narvarte; G Diaz; R Carpentier
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Publication Detail:
Type:  In Vitro; Journal Article    
Journal Detail:
Title:  European journal of pharmacology     Volume:  30     ISSN:  0014-2999     ISO Abbreviation:  Eur. J. Pharmacol.     Publication Date:  1975 Jan 
Date Detail:
Created Date:  1975-06-29     Completed Date:  1975-06-29     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  1254354     Medline TA:  Eur J Pharmacol     Country:  NETHERLANDS    
Other Details:
Languages:  eng     Pagination:  15-22     Citation Subset:  IM    
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MeSH Terms
Descriptor/Qualifier:
Alkaloids / pharmacology*
Animals
Depression, Chemical
Electric Stimulation
Heart Atria / drug effects*
Heart Rate / drug effects
Indoles / pharmacology*
Pyridines / pharmacology
Rats
Time Factors
Chemical
Reg. No./Substance:
0/Alkaloids; 0/Indoles; 0/Pyridines

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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