Preprint volume - SIBM

Pre-print Volume - Posters
VARIOUS TOPICS
L. GALLUS 1 , S. FERRANDO 1 , C. GAMBARDELLA 1,2 , A. DIASPRO 3 , P. BIANCHINI 4 ,
V. PIAZZA 5 , P. RAMOINO 6 , G. TAGLIAFIERRO 1
1 LIBiOM, DIBIO, Univ. of Genoa, Corso Europa, 26 – 16132 Genova, Italia.
Gallus@unige.it
2 Dept. of Animal Biology and Marine Ecology, Univ. of Messina, Italia.
3 The Italian Institute of Technology – IIT Genova, Italia.
4 IFOM-LAMBS/MicroScoBio, DIFI, Univ. of Genoa, Italia.
5 Istit. di Scienze Marine, ICMM, CNR, Genova, Italia.
6 DIPTERIS, Univ. of Genoa, Italia.
IMMUNOHISTOCHEMICAL DISTRIBUTION
OF NMDAR1 RECEPTOR IN THE CYPRID OF BALANUS AMPHITRITE
(=AMPHIBALANUS AMPHITRITE) (CRUSTACEA, CIRRIPEDIA)
DISTRIBUZIONE IMMUNOISTOCHIMICA
DEL RECETTORE NMDAR1 NELLA CIPRIS DI BALANUS AMPHITRITE
(=AMPHIBALANUS AMPHITRITE) (CRUSTACEA, CIRRIPEDIA)
Abstract – In this work, we used immunochemical methods to investigate the occurrence of the NMDA
ionotropic glutamate receptor (NMDAR1) in the cyprid of Balanus amphitrite (=Amphibalanus amphitrite).
Immunoreactivity was detected out of the central nervous system in neuronal and non-neuronal sites. In
fact, NMDAR1 immunoreactivity was seen in thoracic appendages, at level of neuromuscular junctions, as
previously demonstrated in crustaceans, and in antennules. Positive responses were also detected in
ommatidum cells, maybe with non visual function, and in the tegumentary system, probably with non
neural functions.
Key-words: Barnacle cyprid, Glutamate, NMDA receptors, neuromuscular junctions.
Introduction - The ontogenetic cycle of the barnacle Balanus amphitrite (Darwin,
1854) includes a cyprid that binds submerged surfaces by its antennulae and the
secretory product of a cement gland, metamorphosing into a sessile adult. Recently γaminobutyric
acid (GABA) and GABAergic receptors have been localized in the B.
amphitrite cyprid (Gallus et al., 2010). The thoracic occurrence of immunoreactivity at
level of striated muscular fibers agrees with that reported for other crustaceans.
According to data of Feinstein (2001) on crustacean muscle, both GABA and
Glutamate, ionotropic and metabotropic receptors might be distributed in excitatory as
well as inhibitory nerve terminals. Since Feinstein et al. (1998) have identified
occurrence of NMDA-type glutamatergic receptors in crayfish neuromuscular junction,
we have investigated the presence of such molecules receptors in the whole B.
amphitrite cyprid. The occurrence of NMDA receptors might indicate a role for
glutamate in the neuromuscular control in B. amphitrite cyprids.
Materials and methods – Two hundred cyprids from laboratory cultures were
anesthetized with Sandoz-222 (Sigma, USA) (1:1000), fixed, rinsed, dehydrated,
embedded in paraplast and sectioned. Primary Ab was a polyclonal: rabbit Ab, anti
NMDA receptor 1 (NR1-pan) (Millipore, USA). The secondary Ab was a goat antirabbit
conjugated with Alexa Fluor 488 (Green fluorescence - Molecular Probes,
USA). Nuclei were counterstained with propidium iodide (Red fluorescence –
Molecular Probes, USA). The sections were observed by a CLSM DMI6000B-CS
CLSM with a TCS-SP5 AOBS scanning head, (Leica, Germany). Controls:
41 st S.I.B.M. CONGRESS Rapallo (GE), 7-11 June 2010
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