title: The effect of invertebrate hormones and potential hormone inhibitors on the third larval moult of the filarial nematode, Dirofilaria immitis, in vitro.
abstract: The effects of the insect hormones, ecdysone and 20-hydroxyecdysone, certain non-steroidal ecdysteroid agonists (RH compounds) and the inhibitor, azadirachtin, on the timing of the 3rd-stage moult of Dirofilaria immitis were investigated. 20-Hydroxyecdysone and RH 5849 when used at a concentration of 10(-5) M, resulted in a premature timing of this moult. Azadiracthin, at a similar concentration, prevented moulting of most of the larvae to the 4th stage. The results are discussed in relation to the possibility of a hormonal role for ecdysteroids and neuropeptide-like compounds in the control of ecdysis in filarial nematodes, that maybe somewhat comparable to the system which is found in insects.
authors.affiliation: Department of Parasitology, Liverpool School of Tropical Medicine.
authors.forename: E V
authors.initials: EV
authors.lastname: Warbrick
authors.forename: G C
authors.initials: GC
authors.lastname: Barker
authors.forename: H H
authors.initials: HH
authors.lastname: Rees
authors.forename: R E
authors.initials: RE
authors.lastname: Howells
mesh_terms: D000330:Aedes / Q000469:parasitology; D000818:Animals; D004183:Dirofilaria immitis / Q000187:drug effects* / Q000254:growth & development*; D004440:Ecdysone / Q000494:pharmacology; D004441:Ecdysterone / Q000494:pharmacology; D006834:Hydrazines / Q000494:pharmacology; D007301:Insect Hormones / Q000037:antagonists & inhibitors* / Q000494:pharmacology*; D007306:Insecticides / Q000494:pharmacology; D007814:Larva / Q000187:drug effects; D036701:Limonins; D008675:Metamorphosis, Biological / Q000187:drug effects; D014315:Triterpenes / Q000494:pharmacology
chemical_list: D006834:Hydrazines; D007301:Insect Hormones; D007306:Insecticides; D036701:Limonins; D014315:Triterpenes; C056565:1,2-dibenzoyl-tert-butylhydrazine; D004440:Ecdysone; D004441:Ecdysterone; C010329:azadirachtin