Echinoderms: San Francisco, Mooi& Tellord(eds)© 1998Balkema, Rotterdam, ISBN 90 5410 929 7

Presence of the SALMFamide neuropeptides S 1 and S2 in the britdestar Amphipholis squamata: Immunohistochemical and radioimmunoassay

detection .\

/\ - N. De Bremaeker, J. Mallefet & F. Baguet Laboratory of Animal Physiology, Catholic University ofLomain, Belgium M.C.Thomdyke & D.J.Potton Department of Biology, Royal Holloway University of London, UK D.Deheyn Laboratory of Marine Biology, University of Brussels, Belgium

Recendy a novel faimly of echinoderm ACKNOWLEDGEMENTS: neuropepddes, the SALMFamides, has been characterized. Sl and S2 were isolated from radialThis work was supported by a cooperation grant nerve cords of the starfishes Asterias rubens andCGRI-British Council-FNRS. Financial support Asteriasforbesi (Hphick et al. 1991). S3 andfrom S4 FDS (UCL) and FRFC (number 6.231.85), were isolated and sequenced from extractsContribution of the of the "Centre Interuniversitaire de digestive system of the sea cucumba" HolothunaBiologie Marine" (CIBIM). gCabemma (Diaz-Miranda et 1992).al. immunocytochemistry and radio-immunoassay studies have shown'Sl and S2 to be widely REFERENCES distributed in the nervous systems of asteroids, echinoids, and ophiuroids. Physiological Cobb J.L.S. & Stubbs T.R. 1981. The giant experiment, have shown that the neuropepddesneuron system in ophiuroids. I. The general Sl and S2 have neuromodulating effects on the morphology of the radial nerve cords and the luminescence of Amphipholis squamata, a. smaUcircumoral nerve ring. Cell Tissue Res., 219, cosmopolitan ophiuroid (Mallefet et brittle star Ophium nerve ring. The immuno-reactivily patten ophiura. Phil. Trans. R. Soc. Land. B. observed iii the radial nerve cord of one arm 346:433-444. segment is_identical to that of the adjacentMaUefetJ.,DeBremaekerN. arm & Baguet F. 1994. segment. Such segmental oiganization of theNeuromodulatory effects ofGABA, Sl_ & 82, nearve cord was reported previously by CobbPMRFamide and and ANTHO-RFamide on Stubbs (1981) and Ghyootetal. (1994). Amphipholis squamata (Echinodermata) The radioimmunoassay results _from acetoneluminescence. In: A.K. Campbell, L.J.Kricka extracts of A. squamata showed 0.006 pmojes& P.E. of Stanley (eds.), Bioluminescence and Sl/mg wet weight and 0.025 pmoles of S2/mgchemi-luminescence: 109-112. J. WUey & Sons, wet weight. It is interesting to note that thereChichester. seems to be a seasonal variation in Sl and S2 . concentrations.

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