Hydrogen peroxide may serve as a diffusible intermediary messenger under physiological and pathophysiological conditions. H2O2 (1 mM) increased the amplitude of GABAergic miniature inhibitory postsynaptic currents in substantia gelatinosa of the spinal cord. This effect of H2O2 was reversed by the p38 antagonist SB203580, but not by the extracellular signal-regulated kinase 1/2 antagonist PD980...
