AJP - Heart Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Heart Circ Physiol 252: H513-H520, 1987;
0363-6135/87 $5.00
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Tsujimoto, G.
Right arrow Articles by Hoffman, B. B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Tsujimoto, G.
Right arrow Articles by Hoffman, B. B.

AJP - Heart and Circulatory Physiology, Vol 252, Issue 3 513-H520, Copyright © 1987 by American Physiological Society

ARTICLES

Effects of thyroid hormone on beta-adrenergic responsiveness of aging cardiovascular systems

G. Tsujimoto, K. Hashimoto and B. B. Hoffman

We have compared the effects of beta-adrenergic stimulation on the heart and peripheral vasculature of young (2-mo-old) and older (12-mo-old) rats both in the presence and absence of triiodothyronine (T3)-induced hyperthyroidism. The hemodynamic consequences of T3 treatment were less prominent in the aged hyperthyroid rats compared with young hyperthyroid rats (both in intact and pithed rats). There was a decrease in sensitivity of chronotropic responsiveness to isoproterenol in older pithed rats, which was apparently reversed by T3 treatment. The number and affinity of myocardial beta-adrenergic receptor sites measured by [125I]cyanopindolol were not significantly different in young and older control rats; also, beta-receptor density increased to a similar extent in both young and older T3-treated rats. The ability of isoproterenol to relax mesenteric arterial rings, markedly blunted in older rats, was partially restored by T3 treatment without their being any change in isoproterenol-mediated relaxation in the arterial preparations from young rats. The number and affinity of the beta-adrenergic receptors measured in the mesenteric arteries was unaffected by either aging or T3 treatment. The data suggest that effects of thyroid hormone and age-related alterations of cardiovascular responsiveness to beta-adrenergic stimulation are interrelated in a complex fashion with a net result that the hyperkinetic cardiovascular manifestations in hyperthyroidism are attenuated in the older animals.


This article has been cited by other articles:


Home page
 Exp. Biol. Med.Home page
J. Chehade, J. Kim, J. L. Pinnas, and A. D. Mooradian
Age-Related Changes in the Thyroid Hormone Effects on Malondialdehyde-Modified Proteins in the Rat Heart
Experimental Biology and Medicine, October 2, 1999; 222(1): 59 - 64.
[Abstract] [Full Text]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online