Induction of superoxide production in rabbit neutrophils by a stable analogue of GTP

Treatment of rabbit neutrophils with the stable GTP analogue GTP gamma S results in generation of superoxide. Whereas poly-L-arginine, an agent known to damage the plasma membrane, has only a small effect by itself, a strong and synergistic enhancement of superoxide generation is obtained in the presence of GTP gamma S and poly-L-arginine. The effect is potentiated in the presence of NADPH. Other nucleotides, such as GTP, are not effective in inducing superoxide generation. The results indicate that the stable guanine nucleotide GTP gamma S may activate superoxide production in rabbit neutrophils, and that this effect is evident if the plasma membrane has been permeabilized by poly-L-arginine, allowing an easy entry of GTP gamma S into the cell.