Orescanin-Dusić Zorana, Milovanović Slobodan, Blagojević Dusko, Nikolić-Kokić Aleksandra, Radojicić Ratko, Spasojević Ivan, Spasić Mihajlo
Department of Physiology, Institute for Biological Research, Sinisa Stanković, Bulevar Despota Stefana 142, Belgrade, Serbia.
Redox Rep. 2009;14(2):48-54. doi: 10.1179/135100009X392476.
Protamine sulphate causes potassium ion channel-mediated relaxation of spontaneous and calcium ion-induced contractions of the isolated rat uterus. Diethyldithiocarbamate (DDC) potentiated the effect of protamine sulphate. A mechanism for DDC's action was postulated on the basis of its interactions with divalent iron ions and Cu,Zn-SOD. DDC chelates divalent iron ions creating DDC-iron (Fe-DDC) complexes. Fe-DDC forms stable NO-Fe-DDC(2) complexes by NO scavenging and de-nitrosylation processes, which in combination with DDC (5 mM) provoke inhibition of Cu,Zn-SOD resulting in specific oxidative conditions culminating in potassium ion channel opening, membrane hyperpolarisation, inhibition of calcium ion influx and subsequent muscle relaxation. As Fe-DDC and NO-Fe-DDC(2) complexes exclude divalent iron ions from participating in the hydroxyl radical generating Fenton reaction, DDC can also prevent iron-related pathophysiological manifestations. Such permissive roles of DDC open the possibility for application of its pharmacological form (disulfiram) to a wider spectrum of pathophysiological conditions related to smooth muscles.
