title: Inhibitory effects of Selaginella tamariscina on immediate allergic reactions.
abstract: The anti-allergic effects of a 70% ethanol extract from Selaginella tamariscina herb (EST) were evaluated in this study. EST given at the doses of 500 and 1000 mg/kg can inhibit mouse systemic anaphylactic shock induced by compound 48/80 in a dose-dependent manner. It can also dose-dependently block rat homologous passive cutaneous anaphylaxis and skin reactions caused by exogenous histamine and serotonin with a significant difference observed at the dose of 1000 mg/kg. In addition, EST can reduce histamine release from rat peritoneal mast cells triggered by compound 48/80 and an antigen in vitro. When incubated with rat mast cells, the extract (200 microg/ml) can significantly elevate the intracellular cAMP levels. The finding suggests that EST inhibits mast cell-dependent, immediate allergic reactions. Its effects appear to be mediated by reducing the release of vasoactive amines such as histamine from mast cells via stabilizing the cell membrane and weakening the inflammatory action of these amines. Based on these results, Selaginella tamariscina and one of its active components flavonoids may be useful as potential remedies for allergic rhinitis and other allergy-related diseases.
authors.affiliation: Department of Pharmacology, China Pharmaceutical University, China. yuedaicpu@hotmail.com
authors.forename: Yue
authors.initials: Y
authors.lastname: Dai
authors.forename: Paul Pui-Hay
authors.initials: PP
authors.lastname: But
authors.forename: Lee-Man
authors.initials: LM
authors.lastname: Chu
authors.forename: Yiu-Pong
authors.initials: YP
authors.lastname: Chan
mesh_terms: D000707:Anaphylaxis / Q000188:drug therapy*; D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D006636:Histamine Release / Q000187:drug effects*; D008297:Male; D008407:Mast Cells / Q000378:metabolism; D010323:Passive Cutaneous Anaphylaxis / Q000187:drug effects*; D010537:Peritoneum / Q000166:cytology; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D032503:Selaginellaceae
chemical_list: D010936:Plant Extracts; D000242:Cyclic AMP