title: Effect of Syzygium aromaticum extract on immediate hypersensitivity in rats.
abstract: We investigated the effect of aqueous extract of Syzygium aromaticum (L.) Merr. et Perry (Myrtaceae) flower bud (SAFB) on immediate hypersensitivity. SAFB inhibited compound 48/80-induced systemic anaphylaxis in rats (IC50 = 31.25 mg/kg, i.p.). SAFB also inhibited local immunoglobulin E (IgE)-mediated passive cutaneous anaphylactic reaction (IC50 = 17.78 mg/kg, i.v.; IC50 = 19.81 mg/kg, p.o.). When SAFB was pretreated at concentrations ranging from 25 to 1000 mg/kg, the serum histamine levels were reduced in a dose-dependent manner. Moreover, SAFB dose-dependently inhibited histamine release from rat peritoneal mast cells (RPMC) by compound 48/80 or anti-dinitrophenyl IgE. When SAFB was added, the level of cAMP in RPMC transiently and significantly increased about 47-fold at 10 s compared with that of basal cells. These results indicate that SAFB inhibits immediate hypersensitivity by inhibition of histamine release from mast cells in vivo and in vitro.
authors.affiliation: Department of Oriental Pharmacy, College of Pharmacy, Wonkwang University, Chonbuk, South Korea.
authors.forename: H M
authors.initials: HM
authors.lastname: Kim
authors.forename: E H
authors.initials: EH
authors.lastname: Lee
authors.forename: S H
authors.initials: SH
authors.lastname: Hong
authors.forename: H J
authors.initials: HJ
authors.lastname: Song
authors.forename: M K
authors.initials: MK
authors.lastname: Shin
authors.forename: S H
authors.initials: SH
authors.lastname: Kim
authors.forename: T Y
authors.initials: TY
authors.lastname: Shin
mesh_terms: D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D006632:Histamine / Q000097:blood; D006969:Hypersensitivity, Immediate / Q000139:chemically induced / Q000188:drug therapy*; D008407:Mast Cells / Q000187:drug effects / Q000378:metabolism; D010529:Peritoneal Cavity / Q000166:cytology; D010936:Plant Extracts / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D003189:p-Methoxy-N-methylphenethylamine / Q000494:pharmacology
chemical_list: D010936:Plant Extracts; D003189:p-Methoxy-N-methylphenethylamine; D006632:Histamine; D000242:Cyclic AMP