title: Effects of some lignans and neolignans on the development and excretion of Rhodnius prolixus.
abstract: The effects of six lignans and neolignans as inhibitors of ecdysis and on the water balance in fourth-instar larvae of Rhodnius prolixus were studied by oral, topical and continuous contact treatments. The main results may be summarised as follows: (i) burchellin, pinoresinol, sesamin, licarin A and nordihydroguaiaretic acid (NDGA) did not cause feeding inhibition at doses of 100 micrograms/ml blood; podophyllotoxin had no antifeedant effect but caused a high moulting inhibition and significant toxicity when applied either orally or topically; (ii) the highest ecdysis inhibitory effects were observed with pinoresinol and NDGA when applied orally at a dose of 100 micrograms/ml (58% and 50% of moulting inhibition, respectively); burchellin inhibited 30% of the moulting at this concentration; (iii) by topical treatment none of the compounds presented any influence on the moulting cycle; and (iv) podophyllotoxin and burchellin significantly reduced the excretion of the insect in 24 h; the other compounds had no effect on excretion. The implications of these findings in relation to the pertinent biological events in R. prolixus are discussed.
authors.affiliation: Departamento de Bioquímica e Biologia Molecular, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Av. Brasil 5365, Rio de Janeiro, RJ, Brazil.
authors.forename: M M
authors.initials: MM
authors.lastname: Cabral
authors.forename: P
authors.initials: P
authors.lastname: Azambuja
authors.forename: O R
authors.initials: OR
authors.lastname: Gottlieb
authors.forename: E S
authors.initials: ES
authors.lastname: Garcia
mesh_terms: D000818:Animals; D001572:Benzofurans / Q000494:pharmacology; D004149:Dioxoles / Q000494:pharmacology; D005247:Feeding Behavior / Q000187:drug effects; D005663:Furans / Q000494:pharmacology; D007814:Larva / Q000187:drug effects; D019770:Lauraceae; D017705:Lignans / Q000494:pharmacology*; D009637:Masoprocol / Q000494:pharmacology; D010946:Plants, Medicinal; D011034:Podophyllotoxin / Q000494:pharmacology; D012239:Rhodnius / Q000187:drug effects* / Q000254:growth & development* / Q000378:metabolism
chemical_list: D001572:Benzofurans; D004149:Dioxoles; D005663:Furans; D017705:Lignans; C432503:licarin A; C053585:burchellin; D009637:Masoprocol; D011034:Podophyllotoxin; C054125:sesamin; C103298:pinoresinol