Inhibition of immediate allergic reactions by ethanol extract from Plumbago zeylanica stems.
The antiallergic properties of the 70% ethanol extract from Plumbago zeylanica stems (EPZ) were investigated in the present study. The extract (500, 1000 mg/kg, p.o.) dose-dependently inhibited systemic anaphylactic shock induced by compound 48/80 in mice, reduced homologous passive cutaneous anaphylaxis and skin reactions induced by histamine or serotonin in rats, significant differences were observed at the dose of 1000 mg/kg. In vitro, EPZ (5, 20, 50 microg/ml) concentration-dependently reduced histamine release from rat peritoneal mast cells caused by compound 48/80 and antigen. EPZ (50 microg/ml) markedly increased intracellular cAMP content of rat mast cells. These findings demonstrate that EPZ inhibits mast cell-dependent immediate allergic reactions, which is probably mediated by reducing the release of mediators such as histamine from mast cells via elevating intracellular cAMP level and weakening the inflammatory action of mediators.
Dai
Yue
Y
Department of Pharmacology of Chinese Materia Medica, China Pharmaceutical University, Nanjing, China. yuedaicpu@hotmail.com
Hou
Li-Fei
LF
Chan
Yiu-Pong
YP
Cheng
Ling
L
But
Paul Pui-Hay
PP
D000284:Administration, Oral; D000707:Anaphylaxis / Q000188:drug therapy* / Q000276:immunology / Q000517:prevention & control; D000818:Animals; D018926:Anti-Allergic Agents / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D000242:Cyclic AMP / Q000096:biosynthesis; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D000431:Ethanol; D006632:Histamine / Q000494:pharmacology; D006636:Histamine Release / Q000187:drug effects; D066298:In Vitro Techniques; D008297:Male; D008407:Mast Cells / Q000378:metabolism; D051379:Mice; D008813:Mice, Inbred ICR; D010047:Ovalbumin / Q000276:immunology; D010323:Passive Cutaneous Anaphylaxis / Q000187:drug effects; D010529:Peritoneal Cavity / Q000166:cytology; D008517:Phytotherapy; D018547:Plant Stems; D029606:Plumbaginaceae / Q000737:chemistry*; D051381:Rats; D012701:Serotonin / Q000494:pharmacology
D018926:Anti-Allergic Agents; D004365:Drugs, Chinese Herbal; D012701:Serotonin; D000431:Ethanol; D006632:Histamine; D010047:Ovalbumin; D000242:Cyclic AMP