Effect of GSNO on the activity of nNOS and the levels of NO and peroxynitrite (3-NT) in ipsilateral (penumbra) area of the IR brain. nNOS activity at 1 h (a), NO levels at 1 h (b) and peroxynitrite levels (3-NT, IHC [c] and IHC colocalization of 3-NT and neuronal marker NeuN [d]) at 1 h after reperfusion were determined. GSNO were administered 0 h after reperfusion began. NO levels in Sham animals were 39.8 ± 4.2 nmol/mg protein. Data are presented as mean ± SD (n = 5). ***p < 0.001 vs. Sham, ###p < 0.001, #p < 0.05 vs. IR, $$p < 0.01, $p < 0.05 vs. Sham.