Signaling pathways involved in the H2O2-induced vasoconstriction of rat coronary arteries

► H2O2 induces contraction of coronary arteries depending on the arterial size and membrane polarization. ► Contraction response to H2O2 is endothelium-dependent and mediated by COX and thromboxane A2 receptor. ► O2− production and activation of NADPH oxidase are involved in H2O2 vasoconstriction. ► H2O2 contraction involves [Ca2+]i increase and activation of non-L-type and L-type Ca2+ channels. ► MAP and Rho kinases are implicated in H2O2 coronary vasoconstriction.