Significance of the development of inducible nitric oxide synthase in myocardial tissues with acute myocardial infarction

Abstract

To investigate whether the nitric oxide (NO) is involved in the myocardial damage in acute myocardial infarction (AMI), ventricular myocardial tissue of autopsied cases with myocardial infarction was examined by immunohistochemical staining with anti-inducible NO synthase (iNOS) and anti-nitrotyrosine antibody.
The damaged residual myocardium were positively stained with anti-iNOS antibody and anti -nitrotyrosine antibody in AMI. These findings were not obtained in the myocardial tissue of patients who died shortly in the early stage when myocardial cells reveal contraction band necrosis with minimal inflammatory cell infiltration. And also they were not obtained in patients with old myocardial infarction.
Since iNOS development accompanied by cell infiltration was noted in the damaged myocardium and nitrotyrosine was also disclosed in the same area, it is suggested that not only NO but also peroxynitrite is involved in myocardial damage in AMI.