Titre du document / Document title

Studies of peripheral benzodiazepine receptors in mussels: comparison between a polluted and a nonpolluted site

Auteur(s) / Author(s)

BETTI Laura ⁽¹⁾ ; GIANNACCINI Gino ⁽¹⁾ ; NIGRO Marco ⁽²⁾ ; DIANDA Sabina ⁽¹⁾ ; GREMIGNI Vittorio ⁽²⁾ ; LUCACCHINI Antonio ⁽¹⁾ ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

⁽¹⁾ Dipartimento di Psichiatria, Neurobiologia, Farmacologia e Biotecnologie dell'Università di Pisa, Via Bonanno 6, 56126 Pisa, ITALIE
⁽²⁾ Dipartimento di Morfologia Umana e Biologia Applicata dell'Università di Pisa, Via Roma 55, 56126 Pisa, ITALIE

Résumé / Abstract

The aim of this study was to investigate the peripheral benzodiazepine receptors in soft tissue membranes of the mussel Mytilus galloprovincialis from both polluted and nonpolluted seawater populations, using a radioligand specific for this receptor, [³H]PK11195. Mussels were dissected into four body parts-mantle, gills, digestive gland, and muscles-to determine the distribution of tissue-specific peripheral benzodiazepine receptors (PBRs). The specific binding was saturable and reversible. A statistically significant increase (muscle, 537% and mantle, 201%, as absolute percentages) in the maximal number of binding sites (B_max) was found in mussels from the polluted site, compared with mussels from the nonpolluted site. By contrast, the value of the dissociation constant (K_d) at equilibrium does not show a statistically significant variation between the two groups. In competitive experiments of the compounds clonazepam, flumazenil, flunitrazepam, Ro5-4864, PK11195, and protoporphyrin IX, only PK11195 and protoporphyrin IX displaced [³H]PK11195 specifically bound to soft tissue membranes, revealing that the binding sites of peripheral benzodiazepine receptors of mussels have pharmacological properties comparable to those of low vertebrates such as trout. M. galloprovincialis was also tested as an indicator of heavy metal exposure, and metal accumulation in the digestive gland was measured by atomic absorption spectrophotometry (AAS). The contents of Pb, Mn, and Zn in mussels collected off the polluted site were higher than those in mussels from the nonpolluted site. These data suggest that PBRs are present in the soft tissues of the mussel M. galoprovincialis. Here we report preliminary evidence of biochemical alterations in mussels from the polluted site.

Revue / Journal Title

Ecotoxicology and environmental safety   ISSN 0147-6513   CODEN EESADV 

Source / Source

2003, vol. 54, n^o1, pp. 36-42 [7 page(s) (article)] (26 ref.)

Langue / Language

Anglais

Editeur / Publisher

Elsevier, San Diego, CA, ETATS-UNIS  (1977) (Revue)

Mots-clés anglais / English Keywords

Invertebrata ; Mollusca ; Bivalvia ; Water pollution ; Marine environment ; Mediterranean Sea ; Europe ; Italy ; Mytilus galloprovincialis ; Tyrrhenian Sea ; Tuscany ; Coastal zone ; Spatial variation ; Digestive gland ; Biological accumulation ; Ligand binding ; Binding capacity ; Mitochondria ; Benzodiazepine receptor ; Biological indicator ; Toxicity ; Heavy metal ;

Mots-clés français / French Keywords

Invertebrata ; Mollusca ; Bivalvia ; Pollution eau ; Milieu marin ; Mer Méditerranée ; Europe ; Italie ; PK11195 ; Mytilus galloprovincialis ; Mer Tyrrhénienne ; Toscane ; Zone côtière ; Variation spatiale ; Glande digestive ; Accumulation biologique ; Fixation ligand ; Capacité fixation ; Mitochondrie ; Récepteur benzodiazépinique ; Indicateur biologique ; Toxicité ; Métal lourd ;

Mots-clés espagnols / Spanish Keywords

Invertebrata ; Mollusca ; Bivalvia ; Contaminación agua ; Medio marino ; Mar Mediterráneo ; Europa ; Italia ; Mytilus galloprovincialis ; Mar Tirreno ; Toscana ; Zona costera ; Variación espacial ; Glándula digestiva ; Acumulación biológica ; Fijación ligando ; Capacidad de fijación ; Mitocondria ; Receptor benzodiazepínico ; Indicador biológico ; Toxicidad ; Metal pesado ;

Localisation / Location

INIST-CNRS, Cote INIST : 17753, 35400010430164.0060