Hydroxyguanidine sulfate

Hydroxyguanidine sulfate is a substrate found in endothelial cells that reacts with nitric oxide to produce a vasodilating compound. Suppression of this reaction occurs when oxyhaemoglobin is present. In addition, the actions of hydroxyguanidine sulfate is similar to NG-hydroxy-L-arginine resulting in the stabilization and potentiation of nitric oxide. Hydroxyguanidine serves as a specific reduction cosubstrate for the enzyme dopamine β-hydroxylase, used in the conversion of the neurotransmitter dopamine into norepinephrine.