TY - JOUR
T1 - Intrinsic myocyte dysfunction and tyrosine kinase pathway activation underlie the impaired wall thickening of adjacent regions during postinfarct left ventricular remodeling
AU - Melillo, Guido
AU - Lima, João A C
AU - Judd, Robert M.
AU - Goldschmidt-Clermont, Pascal J.
AU - Silverman, Howard S.
PY - 1996/4/1
Y1 - 1996/4/1
N2 - Left ventricular remodeling after infarction is accompanied by dysfunction of regions adjacent to the infarct. We hypothesized that myocyte contractile abnormalities and elongation greater than in remote regions underlie adjacent-region dysfunction in the remodeled ventricle. The activation of the tyrosine kinase pathway, which mediates in vitro hypertrophy by stretch and/or angiotensin, was also assessed in myocytes separately isolated from adjacent and remote regions. Methods and Results. ECG-gated magnetic resonance imaging short-axis images were acquired 2 weeks after coronary ligation in rats. After the rats were killed, myocytes were isolated from animals with large (n=7) and small (n=7) infarcts and from 4 sham-operated controls. Regional wall thickening was correlated with local myocyte function and morphology. Cytochemistry for tyrosine-phosphorylated proteins was performed in myocytes from the same regions. Remodeled ventricles were dilated relative to controls by 93.7%, and wall thickening in adjacent regions was less than in remote regions (27.8 ± 6.11% versus 54.0 ± 10.1%, P
AB - Left ventricular remodeling after infarction is accompanied by dysfunction of regions adjacent to the infarct. We hypothesized that myocyte contractile abnormalities and elongation greater than in remote regions underlie adjacent-region dysfunction in the remodeled ventricle. The activation of the tyrosine kinase pathway, which mediates in vitro hypertrophy by stretch and/or angiotensin, was also assessed in myocytes separately isolated from adjacent and remote regions. Methods and Results. ECG-gated magnetic resonance imaging short-axis images were acquired 2 weeks after coronary ligation in rats. After the rats were killed, myocytes were isolated from animals with large (n=7) and small (n=7) infarcts and from 4 sham-operated controls. Regional wall thickening was correlated with local myocyte function and morphology. Cytochemistry for tyrosine-phosphorylated proteins was performed in myocytes from the same regions. Remodeled ventricles were dilated relative to controls by 93.7%, and wall thickening in adjacent regions was less than in remote regions (27.8 ± 6.11% versus 54.0 ± 10.1%, P
KW - heart failure
KW - magnetic resonance imaging
KW - myocardial infarction
KW - remodeling
KW - tyrosine kinase
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M3 - Article
C2 - 8641035
AN - SCOPUS:9044243751
VL - 93
SP - 1447
EP - 1458
JO - Circulation
JF - Circulation
SN - 0009-7322
IS - 7
ER -