title: Localization of serotonin and its possible role in early embryos of Tritonia diomedea(Mollusca: Nudibranchia).
abstract: A classical neurotransmitter serotonin (5-HT) was detected immunochemically using laser scanning microscopy at the early stages of Tritonia diomedea development. At the one- to eight-cell stages, immunolabeling suggested the presence of 5-HT in the cytoplasm close to the animal pole. At the morula and blastula stages, a group of micromeres at the animal pole showed immunoreactivity. At the gastrula stage no immunoreactive cells were detected, but they arose again at the early veliger stage. Antagonists of 5-HT(2) receptors, ritanserin and cyproheptadine, as well as lipophilic derivatives of dopamine blocked cleavage divisions or distorted their normal pattern. These effects were prevented by 5-HT and its highly lipophilic derivates, serotoninamides of polyenoic fatty acids, but not by the hydrophilic (quaternary) analog of 5-HT, 5-HTQ. The results confirm our earlier suggestion that endogenous 5-HT in pre-nervous embryos acts as a regulator of cleavage divisions in nudibranch molluscs.
authors.affiliation: Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia.
authors.forename: Gennady A
authors.initials: GA
authors.lastname: Buznikov
authors.forename: Lyudmila A
authors.initials: LA
authors.lastname: Nikitina
authors.forename: Elena E
authors.initials: EE
authors.lastname: Voronezhskaya
authors.forename: Vladimir V
authors.initials: VV
authors.lastname: Bezuglov
authors.forename: A O
authors.initials: AO
authors.lastname: Dennis Willows
authors.forename: Leonid P
authors.initials: LP
authors.lastname: Nezlin
mesh_terms: D000818:Animals; D003533:Cyproheptadine / Q000494:pharmacology*; D004298:Dopamine / Q000031:analogs & derivatives / Q000494:pharmacology; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000502:physiology*; D007150:Immunohistochemistry; D008974:Mollusca / Q000166:cytology / Q000196:embryology / Q000502:physiology*; D016713:Ritanserin / Q000494:pharmacology*; D012701:Serotonin / Q000378:metabolism*; D012702:Serotonin Antagonists / Q000494:pharmacology; D017366:Serotonin Receptor Agonists / Q000494:pharmacology
chemical_list: D012702:Serotonin Antagonists; D017366:Serotonin Receptor Agonists; D016713:Ritanserin; D003533:Cyproheptadine; D012701:Serotonin; D004298:Dopamine