Immunopharmacological studies on Picrorhiza kurroa Royle ex Benth. Part VI: Effect on anaphylactic activation events in rat peritoneal mast cells.

Mechanism of inhibition of mast cell anaphylaxis by P. kurroa-extract (PK) treatment in rats was investigated. Mast cell-IgE binding, assessed from induction of passive sensitization, was not affected. Calcium-independent early activation events in mast cell anaphylaxis indicated on inhibitory influence of PK-treatment. Inhibition of membrane-protease release by PK-treatment was suggested by study of gastric secretion and exhibition of saturable synergism with Di-isopropyl fluoro phosphate on inhibition of anaphylactic degranulation. pH-independence of mast cell stabilizing effect negates any PK-influence on phospholipid transmethylation. The results complement findings of earlier studies on indirect effects of PK through alteration of membrane structure/function.