title: Distribution of serotonin-, Gamma-Aminobutyric Acid- and substance P-like immunoreactivity in the central and peripheral nervous system of Mytilus galloprovincialis.
abstract: The distribution of serotonin-, GABA- and substance P-like immunoreactivity has been studied in the cerebral and visceral ganglia and in some peripheral tissues of Mytilus galloprovincialis (Moleusca, Bivalvia). Cerebral ganglia contain a developed serotonin-immunoreactive neuronal subpopulation and numerous GABA-immunoreactive neurons, whereas neurons positive for substance P are sparse. In peripheral tissues innervated by the cerebral ganglia (labial palps and oesophagus) only serotonin-immunoreactive nerve fibers were found. In the visceral ganglia, serotonin- and GABA-immunoreactive neurons are far less numerous than in the cerebral ganglia, whereas several neurons positive for substance P are scattered in all cortical zones. Serotonin-immunoreactive plexuses innervate the posterior adductor muscle and the gill filaments which contain also a developed nerve network positive for substance P. The distribution pattern of the immunoreactive elements in the ganglia and in peripheral territories indicates that GABA should exert only a central action, whereas serotonin and a substance P-like peptide are involved both in central and peripheral neurotransmission.
authors.affiliation: Dipartimento di Fisiologia e Biochimica Generali, sezione di Istologia ed Anatomia Umana, Milano, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Vitellaro-Zuccarello
authors.forename: S
authors.initials: S
authors.lastname: De Biasi
authors.forename: P
authors.initials: P
authors.lastname: Bernardi
authors.forename: A
authors.initials: A
authors.lastname: Oggioní