title: Pharmacology of the serotonin-induced meiosis reinitiation in Spisula solidissima oocytes.
abstract: Germinal vesicle breakdown (GVBD) is the first visible response of the oocyte of Spisula solidissima to the neurohormone serotonin. Pharmacological characterization of this response was performed by using 24 serotonin-related compounds. Dose-response curves were assessed by quantification of GVBD. Rank orders of potency obtained were among agonists: serotonin greater than 8-hydroxy-2-(di-N-propylamino)tetralin hydrobromide greater than 2-methyl-serotonin greater than 1-(3-trifluoromethylphenyl)piperazine; among antagonists; ritanserin ritanserin greater than ICS205930 greater than mianserin = ketanserin = propranolol greater than metoclopramide = yohimbine greater than spiperone. Various other monoaminergic compounds tested were inefficient, demonstrating the specificity of the oocyte response to serotonin. Transduction mechanisms underlying this response were then investigated. Ca2+ appeared to be involved since serotonin induced an increase in the uptake of 45Ca2+ and since it was inefficient in calcium-free sea water. The absence of synergy between serotonin and KCl suggested that both compounds use a common transduction pathway. Exposure of the oocyte to the protein kinase C activator TPA inhibited serotonin-dependent maturation. Our data thus point to an original, previously uncharacterized pharmacological profile and transduction mechanism by which serotonin induces oocyte meiosis reinitiation in Spisula solidissima.
authors.affiliation: Ecole Normale Supérieure, Laboratoire de Biologie Moléculaire et Cellulaire, Lyon, France.
authors.forename: S
authors.initials: S
authors.lastname: Krantic
authors.forename: F
authors.initials: F
authors.lastname: Dube
authors.forename: R
authors.initials: R
authors.lastname: Quirion
authors.forename: P
authors.initials: P
authors.lastname: Guerrier
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000254:growth & development*; D002118:Calcium / Q000502:physiology; D005260:Female; D008540:Meiosis / Q000187:drug effects*; D009865:Oocytes / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D009866:Oogenesis / Q000187:drug effects; D011493:Protein Kinase C / Q000502:physiology; D011985:Receptors, Serotonin / Q000187:drug effects; D012701:Serotonin / Q000494:pharmacology*
chemical_list: D011985:Receptors, Serotonin; D012701:Serotonin; D011493:Protein Kinase C; D002118:Calcium