CYTOSKELETON IMMUNOHISTOCHEMICAL STUDY OF EARLY ISCHEMIC MYOCARDIUM

Previous studies on cytoskeletal changes of in vitro and in vivo anima l models of ischemic myocardium have suggested the possibility of usin g alterations in cytoskeleton proteins as an early marker for the post -mortem diagnosis of myocardial ischemia in cases of sudden death due to coronary artery disease (CAD). In the present study, using the tech nique of ABC-immunohistochemistry, we examine the changes of three cyt oskeletal proteins: vinculin, desmin and alpha-actinin in human myocar dial samples taken from 14 cases of CAD sudden death and 13 cases of n on-CAD death. Results of these examinations are compared with immunohi stochemical changes of myoglobin and histochemical staining of hematox ylin and eosin and phosphotungstic acid, and Masson trichrome. Patchy and extensive loss of the three cytoskeletal proteins was demonstrated in the myocardium of victims who died 1 h or later following the onse t of symptoms of ischemic myocardium. The pattern of cytoskeleton chan ge is equivocal in the cases of CAD who died less than 1 h after the o nset of symptoms and of the cases of non-CAD. In these cases, no signi ficant histological change was observed. With less non-specific backgr ound changes and stronger positive staining, immunohistochemical stain ing of the three cytoskeletal proteins is more reliable than myoglobin , which has attracted the attention of many pathologists searching for anatomic evidence of ischemic myocardium in coronary artery disease.