Inhibitions of mast cell-derived histamine release by different Flos Magnoliae species in rat peritoneal mast cells.

Flos Magnoliae (FM) is a commonly used Chinese medicinal herb for symptomatic relief of allergic rhinitis, sinusitis and headache. A number of FM species have been used as substitutes or adulterants for clinical application, although the differences in their pharmacological actions have not been reported. The present study investigated the effects of six identified FM species M. biondii, M. denudata, M. kobus, M. liliflora, M. sargentiana and M. sprengeri, as well as the marker compounds magnolin and fargesin on compound 48/80-induced histamine release in rat peritoneal mast cells (RPMC) in vitro. Ethanolic extracts of all FM species produced a concentration-dependent inhibition of compound 48/80-induced histamine release in RPMC. The rank order of the IC(50)s was M. biondii