Fibronectin Penetration into Heart Myocytes Subjected to Experimental Ischemia by Coronary Artery Ligation

Department of Anatomy and Cell Biology, University of Bergen, Norway.
Acta Anatomica 02/1995; 152(2):119-26. DOI: 10.1159/000147690
Source: PubMed


Using confocal microscopy and immunocytochemistry we have studied early changes in distribution of fibronectin (FN) in myocardial cells of rats subjected to experimental acute myocardial ischemia (AMI) by coronary ligation for several periods of 0.5 h to 6 days. In sham-operated and nonoperated rats, FN was present in the interstitium around the myocytes, and in their transverse tubules (TT). Already after 0.5 h of ischemia there was a well-defined increase of immunoreactive FN in focal areas of the interstitium of the hypoperfused portion, and distinct penetration into adjacent myocytes. The early penetration of FN into myocytes appears to follow a path through the TT, with a codistribution with actin in the I bands. This process precedes a total and diffuse infiltration of FN into the cytoplasm of disintegrating myocytes at later stages of coronary occlusion.

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    • "Two extracellular matrix (ECM) molecules of human mesenchymal stem cells are important for stem cell survival and differentiation towards other lineages: laminin and fibronectin (Hashimoto et al. 2006; Salasznyk et al. 2004; Wijelath et al. 2004). Both these proteins are expressed in the normal heart and increase after MI (Froen and Larsen 1995; Knowlton et al. 1992; Willems et al. 1996). In vivo, an effect of these ECM molecules on stem cell survival and differentiation can be expected if stem cell therapy is applied once these proteins have accumulated. "
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