Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Effects of toxic extracts and purified borbotoxins from Prorocentrum borbonicum (Dinophyceae) on vertebrate neuromuscular junctions
Autore:
Ten-Hage, L; Robillot, C; Turquet, J; Le Gall, F; Le Caer, JP; Bultel, V; Guyot, M; Molgo, J;
Indirizzi:
Inst Fed Neurobiol Alfred Fessard, CNRS UPR 9040, Neurobiol Cellulaire & Mol Lab, F-91198 Gif Sur Yvette, France Inst Fed Neurobiol Alfred Fessard Gif Sur Yvette France F-91198 , France Agence Rech & Valorisat Marine, F-97490 Ste Clotilde, France Agence Rech &Valorisat Marine Ste Clotilde France F-97490 tilde, France Ecole Super Phys & Chim Ind Ville Paris, CNRS ERS 657, Lab Environm & ChimAnalyt, F-75005 Paris, France Ecole Super Phys & Chim Ind Ville Paris Paris France F-75005 ris, France Natl Museum Nat Hist, CNRS ESA 8041, Lab Chim Substances Nat, F-75005 Paris, France Natl Museum Nat Hist Paris France F-75005 ces Nat, F-75005 Paris, France Natl Museum Nat Hist, Lab Cryptogam, F-75005 Paris, France Natl Museum NatHist Paris France F-75005 yptogam, F-75005 Paris, France
Titolo Testata:
TOXICON
fascicolo: 2, volume: 40, anno: 2002,
pagine: 137 - 148
SICI:
0041-0101(200202)40:2<137:EOTEAP>2.0.ZU;2-S
Fonte:
ISI
Lingua:
ENG
Soggetto:
OKADAIC ACID PRODUCTION; CORAL-REEF ECOSYSTEM; MARINE DINOFLAGELLATE; BENTHIC DINOFLAGELLATE; INDIAN-OCEAN; PALYTOXIN; LIMA;
Keywords:
benthic dinoflagellates; borbotoxin; mass spectrometry; neuromuscular junction; Prorocentrum borbonicum; toxicity;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
25
Recensione:
Indirizzi per estratti:
Indirizzo: Molgo, J Inst Fed Neurobiol Alfred Fessard, CNRS UPR 9040, Neurobiol Cellulaire & Mol Lab, 1 Ave Terrasse, F-91198 Gif Sur Yvette, France Inst Fed Neurobiol Alfred Fessard 1 Ave Terrasse Gif Sur Yvette France F-91198
Citazione:
L. Ten-Hage et al., "Effects of toxic extracts and purified borbotoxins from Prorocentrum borbonicum (Dinophyceae) on vertebrate neuromuscular junctions", TOXICON, 40(2), 2002, pp. 137-148

Abstract

Benthic dinoflagellates of the genus Prorocentrum are common in tropical and subtropical water and several species produce phycotoxins potentially involved in human toxic outbreaks. The toxic dinoflagellate Prorocentrum borbonicum collected at La Reunion Island (France) was cultured in laboratory. A crude extract of the organism displayed significant toxicity in mice characterized by progressive limb paralysis, severe dyspnea, and death, and thetoxicity was retained, after partition, in the extract's butanol-soluble fraction (BSF). Electrophysiological experiments characterizing the fraction's effect on isolated vertebrate neuromuscular preparations revealed that it depolarizes the muscle membrane and reduces the driving force for endplate potentials (EPPs) evoked by nerve stimulation, blocking directly- and indirectly-elicited muscle twitches. The depolarization induced by P. borbonicum BSF was not due to Na+ influx through voltage-dependent Na+ channels, since tetrodotoxin neither prevented nor suppressed the depolarization. However, ouabain, a specific ligand of the Na/K ATPase, reduced the depolarization. These results suggest the presence of palytoxin-like compounds in the fraction. HPLC-MS and MSIMS analysis showed the presence of several toxins having identical UV absorbance, among which two new isomeric toxins, borbotoxin-A and -B, of molecular mass of 1037.6 Da were isolated. The purified borbotoxin-A, had no effect on the resting membrane potential of muscle fibers and did not affect directly-elicited muscle twitches. However, the toxin reduced nerve-evoked muscle twitches, in a dose-dependent manner, reduced EPPs' amplitudes and completely blocked miniature endplate potentials. Theseobservations suggest that the main action of borbotoxin-A is to block post-synaptic nicotinic ACh receptors. (C) 2001 Elsevier Science Ltd. All rights reserved.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 29/01/20 alle ore 19:15:37