A toxic substance from the sea urchin Toxopneustes pileolus induces histamine release from rat peritoneal mast cells.

A toxic substance (P-II fraction), fractionated from the pedicellariae of the sea urchin Toxopneustes pileolus, dose-dependently caused the histamine release from rat peritoneal mast cells. The histamine release induced by P-II fraction increased with time, while compound 48/80 caused a more rapid histamine release. The dose-response curve for P-II fraction was studied with concentration 0.03-2.0 mg/ml. This reaction was dependent on Ca2+ and temperature. When glucose (5.5 mM) was omitted during the incubation step, the histamine release induced by P-II fraction was significantly reduced as compared to that of compound 48/80. Pyruvate reversed this reduction. On the other hand, the histamine release induced by P-II fraction was effectively potentiated by the addition of glucose (11.0 mM), but not that by compound 48/80. These results suggest that P-II fraction-induced histamine release differs from that of compound 48/80 disregards to the effects of glucose, because this histamine release appears to be more sensitive to the glycolytic pathway than compound 48/80-induced histamine release.