title: Effect of methyl farnesoate, alone and in combination with other hormones, on ovarian growth of the red swamp crayfish, Procambarus clarkii, during vitellogenesis.
abstract: The effect of methyl farnesoate (MF) on the ovaries of female red swamp crayfish, Procambarus clarkii, undergoing vitellogenesis was determined both in vivo and in vitro. The in vivo assay showed a positive effect of MF on oocyte growth when injected alone and in combination with 17 beta-estradiol, but not in combination with JHIII or 17 alpha-hydroxyprogesterone. A higher level of incorporation of labeled leucine was induced by MF on isolated pieces of ovary. The same effect was seen when ovary and mandibular organ (MO) were coincubated. These results suggest that MF stimulated the synthesis of vitellin in the ovary of crayfish. In vitro, 17 alpha-hydroxyprogesterone completely suppressed the stimulatory action of the MO on the ovary, suggesting a competitive inhibition between 17 alpha-hydroxyprogesterone and MF on the ovary and/or a negative feedback by that steroid on the MO.
authors.affiliation: Animal Physiology Laboratory, FCEyN, University of Buenos Aires, Ciudad Universitaria, Buenos Aires, C1428EHA, Argentina.
authors.forename: Enrique M
authors.initials: EM
authors.lastname: Rodríguez
authors.forename: Laura S
authors.initials: LS
authors.lastname: López Greco
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Medesani
authors.forename: Hans
authors.initials: H
authors.lastname: Laufer
authors.forename: Milton
authors.initials: M
authors.lastname: Fingerman
mesh_terms: D000818:Animals; D003400:Astacoidea / Q000502:physiology*; D005231:Fatty Acids, Unsaturated / Q000737:chemistry / Q000494:pharmacology*; D005260:Female; D006728:Hormones / Q000494:pharmacology*; D007605:Juvenile Hormones / Q000494:pharmacology*; D007930:Leucine / Q000378:metabolism; D009865:Oocytes / Q000187:drug effects / Q000254:growth & development; D009924:Organ Culture Techniques; D010053:Ovary / Q000187:drug effects / Q000254:growth & development*; D013237:Stereoisomerism; D014818:Vitellogenesis / Q000502:physiology*
chemical_list: D005231:Fatty Acids, Unsaturated; D006728:Hormones; D007605:Juvenile Hormones; C032429:methyl farnesoate; D007930:Leucine