The evaluation of antianaphylactic effect of Oryza sativa L. in rats.

This study was carried out to examine the effect of methanol extract of Oryza sativa L. (Dong-Jin in Korean, abbreviate as Os-DJ hereafter) on anaphylaxis. Os-DJ (10(-5) to 1 g/kg) dose-dependently inhibited systemic anaphylaxis induced by compound 48/80 in rats. When Os-DJ was pretreated at concentration ranging from 10(-5) to 1 g/kg, the serum histamine levels were reduced in a dose-dependent manner. Os-DJ (1 g/kg) also significantly inhibited local anaphylaxis activated by anti-dinitrophenyl (DNP) IgE. Moreover, Os-DJ dose-dependently inhibited the histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. These results indicate that Os-DJ possess antianaphylactic activity by inhibition of histamine release from mast cells in vivo and in vitro.