Specific transport of S-nitrosocysteine in human red blood cells: Implications for formation of S-nitrosothiols and transport of NO bioactivity within the vasculature

The transport of various S-nitrosothiols, NO and NO donors in human red blood cells (RBC) and the formation of erythrocytic S-nitrosoglutathione were investigated. Of the NO species tested only S-nitrosocysteine was found to form S-nitrosoglutathione in the RBC cytosol. l-Serine, l-cysteine and l-lysine inhibited formation of S-nitrosoglutathione. Incubation of RBC pre-incubated with S-[15N]nitroso-l-cysteine with native plasma or platelet-rich plasma led to formation of S-[15N]nitrosoalbumin and inhibited platelet aggregation, respectively. The specific transporter system of S-nitroso-l-cysteine in the RBC membrane may have implications for formation of S-nitrosoalbumin and S-nitrosohemoglobin and for transport of NO bioactivity within the vasculature.