The suppressive mechanism of histamine release from rat peritoneal mast cells of iodine-enriched eggs.

We investigated the antiallergic activity of iodine-enriched egg by using rat peritoneal exudate cells. The effects were evaluated by the inhibition ratio of these compounds on histamine release from rat peritoneal exudate cells. Lipid and water-soluble fractions, which were separated from iodine-enriched egg yolk, were used for all experiments. Lipid fractionation of iodine-enriched eggs inhibited histamine release by compound-48/80 in a dose-dependent manner. Lipid fractionation of ordinary eggs had no effect. Neither the water-soluble fraction of iodine-enriched eggs nor ordinary eggs inhibited compound-48/80 induced histamine release. Neither lipid nor soluble fraction of iodine-enriched eggs inhibited histamine release in peritoneal exudate cells with Ca ionophore A23187 stimulation. The same fractions of ordinary eggs were also unable to inhibit histamine release. The lipid fraction, furthermore, was isolated to neutral and polar lipid fractionation. Although both neutral and polar lipid fractionation inhibited histamine release, the effect was dose-dependent in only neutral lipid fractionation. Neither fractions of ordinary egg inhibited histamine release. In conclusion, the components inhibiting histamine release in rat peritoneal exudate cells exist in the neutral lipid fraction of iodine-enriched eggs.