PMID: 8945887Nov 1, 1996Paper

Short- and long-term effects of neonatal hypo- and hyperthyroidism on coronary arterioles in rat

The American Journal of Physiology
M I Heron, K Rakusan

Abstract

Neonatal hypo- and hyperthyroid effects on coronary arteriolar geometry were examined in newborn male Sprague-Dawley rats treated for 12 or 28 days with either triiodothyronine or propylthiouracil. Long-term effects were assessed in weaned rats 52 days after stopping treatment. Influence of both neonatal conditions was more pronounced after 28 days. Neonatal hyperthyroidism induced cardiac hypertrophy; neonatal hypothyroidism attenuated cardiac growth. Hyperthyroid rats had similar arteriolar and capillary numerical densities and arteriolar length density but significantly greater (P < 0.05) total arteriolar length than control. Hypothyroid rats had similar arteriolar numerical and length densities, greater capillary numerical density (P < 0.05), but markedly lower total arteriolar length (P < 0.01) than control. Results suggest that neonatal hyperthyroidism stimulates arteriolar and capillary growth, whereas neonatal hypothyroidism attenuates arteriolar but not capillary growth. After cessation of treatment, total arteriolar length in previously hyperthyroid rats did not change despite increased cardiac mass, whereas previously hypothyroid rats demonstrated marked increases in both cardiac mass and total arteriolar length (P <...Continue Reading

Citations

Jul 19, 2005·American Journal of Physiology. Heart and Circulatory Physiology·Wissam I KhalifeA Martin Gerdes
Dec 5, 2006·American Journal of Physiology. Heart and Circulatory Physiology·Karel RakusanBohuslav Ostadal
Feb 17, 2001·American Journal of Physiology. Heart and Circulatory Physiology·K RakusanF Kolar
Feb 24, 2015·Journal of Endocrinological Investigation·L RodríguezA Fellet

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