A Thyroid Hormone Analog Stimulates Angiogenesis in the Post-infarcted Rat Heart

doi:10.1006/jmcc.1998.0671

Journal of Molecular and Cellular Cardiology

Volume 30, Issue 5, May 1998, Pages 923-932

https://doi.org/10.1006/jmcc.1998.0671 Get rights and content

Abstract

In view of the evidence that thyroid hormone administration has angiogenic effects on the hypertrophic myocardium, we tested the hypothesis that the capillary supply in the hypertrophic myocardium surviving infarction would be improved by administration of the thyroid hormone analog, diiodothyroproprionic acid (DITPA). We administered DITPA (MI-DITPA) or saline (MI-saline), s.c., to rats for 10 days following experimental infarction of the left ventricle (LV). Morphometric methods were used to assess capillarity and myocyte cross-sectional area in three regions of the left ventricle: (1) border (next to the scar of infarction); (2) adjacent (next to the border); and (3) remote (interventricular septum). Infarct size ranged from 20–85% of the LV free-wall, and both groups had similar mean infarct size. Capillary length density (L_v) was significantly higher in the remote region of the treated group than in the MI-saline rats. L_vin the border region, which experienced the most marked increase in cardiocyte cross-sectional area, was not significantly lower than in the other regions, indicating a more marked angiogenic response. In hearts with large infarcts (≥40%) L_vin the border region was higher in the DITPA group than in the non-treated rats. In the MI-DITPA group, cardiocyte size in the border region was positively correlated with that of the other regions, which contrasts with the negative correlations noted for the MI-saline rats. These data suggest that DITPA therapy (1) may improve maximal perfusion potential of the hypertrophied myocardium surviving a myocardial infarction, and (2) is selectively effective in the border region of hearts with large infarcts.

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^☆: Please address all corrrespondence to: Robert J. Tomanek, Dept Anatomy and Cell Biology, Bowen Science Bldg, University of Iowa, Iowa City, IA 52242, USA

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Regular ArticleA Thyroid Hormone Analog Stimulates Angiogenesis in the Post-infarcted Rat Heart☆

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Regular Article
A Thyroid Hormone Analog Stimulates Angiogenesis in the Post-infarcted Rat Heart☆