[Myofibroblasts in a myocardial infarct zone].
Electron microscopy and immunomorphological studies were made to explore the scar 2, 3, 4, 5, 7, 9, 11, 30, 45, 60 and 120 days after myocardial infarction in white rats. After 3-5 days there was a poor response to smooth muscle myosin in some of elongate cells of the postinfarction scar. The response was found to be remarkably enhanced after 11 days. Myofibroblasts with an ultrastructure characteristic of activated fibroblasts were found in the scar by using electron microscopy after 3-5 days of the experiment. They also exhibited some properties typical of the smooth cell ultrastructure, containing myofilament bundles with dense bodies along the cytoplasm periphery, as well as the fragments of the basal membrance. In the later periods of the experiment, myofibroblasts were more closely related to smooth muscle cells in ultrastructure. The origin and function of myofibroblasts in the postinfarction scar are discussed.
D000818:Animals; D002921:Cicatrix / Q000648:ultrastructure; D005347:Fibroblasts / Q000648:ultrastructure*; D005455:Fluorescent Antibody Technique; D008297:Male; D008854:Microscopy, Electron; D009130:Muscle, Smooth / Q000648:ultrastructure; D009203:Myocardial Infarction / Q000378:metabolism / Q000473:pathology*; D009206:Myocardium / Q000378:metabolism / Q000648:ultrastructure*; D009218:Myosins / Q000378:metabolism*; D051381:Rats
D009218:Myosins
Miofibroblasty v zone infarkta miokarda.