Syzygium Aromaticum Extract

We examined the effect of the aqueous extract of Syzygium aromaticum (L.) Merr. And Perry (Myrtaceae) floral bud (SAFB) in immediate hypersensitivity. SAFB inhibited by compound 48/80 induces systemic anaphylaxis in rats (IC 50 = 31.25 mg / kg, i.p.). SAFB inhibited local immunoglobulin E (IgE) mediated passive cutaneous anaphylaxis (IC 50 = 17.78 mg / kg, i V, IC 5 0 = 19.81 mg / kg, po). If SAFB was pretreated at a concentration in the range of 25 to 1000 mg / kg, serum histamine levels were reduced in a dose-dependent manner. Additionally SAFB inhibited the release of peritoneal mast cell rat histamine (RPMC) by the 48/80 compound or anti-dinitrophenyl-dependent IgE dose. If SAFB is added, cAMP levels increased in RPMC temporarily and significantly at both 47 within 10 seconds, relative to basal cells. These results show that SAFB inhibits immediate hypersensitivity by inhibiting the release of histamine by mast cells in vivo and in vitro.