Document Detail


Thyroxine-induced left ventricular hypertrophy in the rat. Anatomical and physiological evidence for angiogenesis.
MedLine Citation:
PMID:  2412724     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
We examined anatomical and physiological responses of the left coronary vascular system to thyroxine-induced myocardial hypertrophy. Wistar-Kyoto rats (1 and 5 months old) were administered thyroxine (0.25 mg/kg per day) or the saline vehicle (sham-treated controls) for 2 months. At the ages of 3 and 7 months, each group of animals was used for one of three experimental protocols: determination of numerical capillary density in perfusion-fixed hearts, measurement of coronary reactive hyperemic responses following a 20-second coronary occlusion (peak-to-resting blood flow velocity) as an index of coronary reserve, and assessment of myocardial perfusion under resting conditions and during maximum coronary dilation (dipyridamole infusion) for the calculation of minimum coronary resistance per unit weight of the left ventricle or minimum coronary resistance of the total left ventricle. In both groups of thyroxine-treated animals, the left ventricular weight-to-body weight ratio increased by 35-40%. Capillary density of the 3- and 7-month-old Wistar Kyoto controls was 4467 +/- 352 (mean +/- SEM) and 4029 +/- 143 capillaries/mm2, respectively, but was increased significantly in the thyroxine-treated animals to 6052 +/- 409 capillaries/mm2 (3-month) and 4654 +/- 201 capillaries/mm2 (7-month). In both age control groups, the peak-to-resting blood flow velocity ratio was about 2.2. This index of coronary reserve was not changed in the thyroxine-treated animals. Myocardial perfusion measurements were limited to the 7-month-old animals.(ABSTRACT TRUNCATED AT 250 WORDS)
Authors:
W M Chilian; R D Wangler; K G Peters; R J Tomanek; M L Marcus
Related Documents :
17709654 - Role of xanthine oxidoreductase in the reversal of diastolic heart failure by candesart...
1828034 - Morphometric, histochemical and autoradiographic studies on myocardial cells in experim...
15659304 - Intravenous administration of conivaptan hydrochloride improves cardiac hemodynamics in...
712614 - Effects of pharmacological intervention on infarct size following induced myocardial in...
22798524 - Cardiomyocyte gtp cyclohydrolase 1 and tetrahydrobiopterin increase nos1 activity and a...
23397334 - The tei index and asymptomatic myocarditis in children with severe dengue.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Circulation research     Volume:  57     ISSN:  0009-7330     ISO Abbreviation:  Circ. Res.     Publication Date:  1985 Oct 
Date Detail:
Created Date:  1985-11-19     Completed Date:  1985-11-19     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  0047103     Medline TA:  Circ Res     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  591-8     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Blood Flow Velocity / drug effects
Blood Pressure / drug effects
Body Weight
Capillaries / pathology
Cardiomegaly / chemically induced,  complications*
Coronary Circulation
Coronary Vessels / pathology,  physiopathology
Dipyridamole / pharmacology
Heart Rate / drug effects
Heart Ventricles / pathology
Hyperemia / physiopathology
Male
Neovascularization, Pathologic / etiology*,  pathology,  physiopathology
Organ Size
Perfusion
Rats
Rats, Inbred WKY
Thyroxine* / pharmacology
Vascular Resistance
Vasodilation
Grant Support
ID/Acronym/Agency:
HL 06496/HL/NHLBI NIH HHS; HL 20827/HL/NHLBI NIH HHS; HL14388/HL/NHLBI NIH HHS
Chemical
Reg. No./Substance:
58-32-2/Dipyridamole; 7488-70-2/Thyroxine

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


Previous Document:  Lidocaine's negative inotropic and antiarrhythmic actions. Dependence on shortening of action potent...
Next Document:  Gabexate mesilate and camostate: new inhibitors of phospholipase A2 and their influence on the alpha...