title: Carnosine as a regulator of soluble guanylate cyclase.
abstract: The molecular mechanism of the participation of carnosine in the functioning of soluble guanylate cyclase is discussed. It is shown that carnosine inhibits the activation of soluble guanylate cyclase by sodium nitroprusside and a derivative of furoxan--1,2,5-oxadiazolo-trioxide (an NO donor). However, carnosine has no effect on stimulation of the enzyme by a structural analog of the latter compound, a furazan derivative (1,2,5-oxadiazolo-dioxide) that is not an NO donor; nor was carnosine involved in the enzyme activation by protoporphyrin IX, whose stimulatory effect is not associated with the guanylate cyclase heme. The inhibition by carnosine of guanylate cyclase activation by an NO donor is due to the interaction of carnosine with heme iron with subsequent formation of a chelate complex. It was first demonstrated that carnosine is a selective inhibitor of NO-dependent activation of guanylate cyclase and may be used for suppression of activity of the intracellular signaling system NO-soluble guanylate cyclase-cGMP, whose sharp increase is observed in malignant tumors, sepsis, septic shock, asthma, and migraine.
authors.affiliation: Institute of Biomedical Chemistry, Russian Academy of Medical Sciences, Moscow, 119832 Russia.
authors.forename: I S
authors.initials: IS
authors.lastname: Severina
authors.forename: O G
authors.initials: OG
authors.lastname: Bussygina
authors.forename: N V
authors.initials: NV
authors.lastname: Pyatakova
mesh_terms: D001792:Blood Platelets / Q000201:enzymology; D002336:Carnosine / Q000502:physiology*; D006162:Guanylate Cyclase / Q000378:metabolism*; D006801:Humans; D012995:Solubility
chemical_list: D002336:Carnosine; D006162:Guanylate Cyclase