title: The influence of the sesquiterpene lactones from Geigeria on mast cell degranulation.
abstract: The sesquiterpene lactones isolated from Geigeria were found to be incapable of inducing rat peritoneal mast cell degranulation at levels of 0.3-1.6 mM. The sulphydryl reagent, N-ethylmaleimide, too was unable to trigger mast cell secretion. Instead, it was observed that these compounds inhibited the release of histamine induced by Compound 48/80. Pretreatment of the lactones and N-ethylmaleimide with the amino acid, L-cysteine, reduced their inhibition ability of histamine release to a considerable extent, but not completely. Geigerin(V), which lacks an alpha-methylene group and the chemically prepared cysteine-adduct of dihydrogriesenin(I), were also capable of inhibiting mast cell secretion by Compound 48/80, but to a lesser extent.
mesh_terms: D000478:Alkylation; D000818:Animals; D003545:Cysteine / Q000494:pharmacology; D005033:Ethylmaleimide / Q000494:pharmacology; D006636:Histamine Release / Q000187:drug effects; D007783:Lactones / Q000494:pharmacology*; D008297:Male; D008407:Mast Cells / Q000187:drug effects*; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012717:Sesquiterpenes / Q000494:pharmacology*; D045789:Sesquiterpenes, Guaiane; D019284:Thapsigargin; D003189:p-Methoxy-N-methylphenethylamine / Q000037:antagonists & inhibitors
chemical_list: D007783:Lactones; D010936:Plant Extracts; D012717:Sesquiterpenes; D045789:Sesquiterpenes, Guaiane; C053303:vermeerin; C011124:tenulin; C052634:dihydrogriesenin; D003189:p-Methoxy-N-methylphenethylamine; C053304:geigerin; C001329:helenalin; C049171:ivalin; C046319:thapsigargicin; D019284:Thapsigargin; C018119:odoratin; C015288:hymenovin; D003545:Cysteine; D005033:Ethylmaleimide