Proliferating cell nuclear antigen (PCNA) and apoptosis in hyperacute and acute myocardial infarction.

The aim of this study was to determine whether cell proliferation and/or apoptotic cell death occur in hyperacute and acute infarction. Proliferating cell nuclear antigen (PCNA) and apoptosis were investigated in ten autoptic hearts within a few hours of infarction and in three normal hearts as controls. The PCNA Labeling Index (PCNA-LI) ranged from 0 to 3.1 in hyperacute infarction (mean 1.38), from 0.3 to 4 in acute infarction (mean 2.04) and from 0 to 1.2 in controls (mean 0.7). Although the results were not statistically significant, PCNA-LI was higher in acute than in hyperacute myocardial infarctions; and it was higher in hyperacute infarctions than in controls. Regarding apoptosis, the Apoptotic Index (AI) in hyperacute infarctions ranged from 0.7 to 3 (mean 1.78), in acute infarctions from 0.9 to 5 (mean 3.24) and in controls from 0 to 0.4 (mean 0.1). The AI was significantly higher in hyperacute and acute infarctions than in controls (p < 0.05).