Document Detail

Norepinephrine turnover in the heart and spleen of the cardiomyopathic Syrian hamster.
MedLine Citation:
PMID:  1192577     Owner:  NLM     Status:  MEDLINE    
Although a reduction in myocardial norepinephrine stores in cardiac hypertrophy and congestive failure is well documented, norepinephrine turnover has been inadequately studied in such hearts. We compared norepinephrine turnover in control and cardiomyopathic hamsters by following the decline in specific activity of myocardial norepinephrine after labelling with an intraperitoneal tracer dose of 3H-norepinephrine. Adult myocardial norepinephrine concentrations were not attained until 4 weeks of age in both strains. There was no difference in the rate of constant (K) for myocardial norepinephrine turnover (0.107+/-0.004 hours-1 vs. 0.100+/-0.005 hours-1) in the two strains of hamsters during the neonatal period. In young control hamsters, K fell to 0.064+/-0.004 hours-1, but that for age-matched hamsters with mild cardiac hypertrophy was 0.102+/-0.001 hours-1 (P less than 0.001). There was little change in K as control hamsters aged. With the development of more severe hypertrophy in cardiomyopathic hamsters, cardiac norepinephrine decreased and resting K rapidly increased to approach the value obtained when hamsters were subjected to immobilization stress (0.302+/-0.013 hours-1). The maximum achievable K remained the same for both control and dystrophic hamsters even during terminal disease. Prolonged immobilization led to a reduction in cardiac norepinephrine in both strains. Ganglionic blockade of failing hamsters completely restored the levels of both cardiac norepinephrine and K to control values. Splenic noradrenergic nerves showed no change in K, norepinephrine content, or maximum K during cardiac decompensation. We conclude that, in the late stages of hamster cardiomyopathy, there is a progressive and possibly specific increase in cardiac sympathetic tone which leads to a concomitant decrease in cardiac norepinephrine. With the loss of sympathetic reserve, congestive failure supervenes.
M J Sole; C M Lo; C W Laird; E H Sonnenblick; R J Wurtman
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Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Circulation research     Volume:  37     ISSN:  0009-7330     ISO Abbreviation:  Circ. Res.     Publication Date:  1975 Dec 
Date Detail:
Created Date:  1976-02-26     Completed Date:  1976-02-26     Revised Date:  2008-11-21    
Medline Journal Info:
Nlm Unique ID:  0047103     Medline TA:  Circ Res     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  855-62     Citation Subset:  IM    
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MeSH Terms
Cardiomyopathies / metabolism*
Chlorisondamine / pharmacology
Disease Models, Animal*
Guinea Pigs
Heart Failure / metabolism
Heart Ventricles / metabolism
Myocardium / metabolism*
Norepinephrine / metabolism*
Spleen / metabolism*
Stress, Physiological / metabolism
Reg. No./Substance:
10028-17-8/Tritium; 51-41-2/Norepinephrine; 7701-62-4/Chlorisondamine

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

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