NMDA-like receptors in the nervous system of the crab

HEPP Y.; CARBO TANO M; MARIA EUGENIA PEDREIRA; FREUDENTHAL RAMIRO

JOURNAL OF COMPARATIVE NEUROLOGY

WILEY-LISS, DIV JOHN WILEY & SONS INC

Lugar: New York; Año: 2012 vol. 521 p. 2279 - 2297

0021-9967

N-Methyl-D-aspartate receptors (NMDARs) are involved in learning and memory processes in vertebrates and invertebrates. In Neohelice granulata,NMDARs are involved in the storage of associative memories (Pedreira et al., 2002; Troncoso and Maldonado, 2002; Pérez-Cuesta et al., 2007). The aim of this work was to characterise this type of glutamate receptor in Neohelice and to describe its distribution in the central nervous system (CNS). As a first step, a detailed study of the CNS of Neohelice granulata was performed at a neuropil level, with special focus on one of the main structures involved in this type of memory, the supraoesophageal ganglion, called central brain. The characterisation of the NMDAR was achieved by identifying the essential subunit of these receptors, the NR1-like subunit. The NR1-like signals were found via Western blot and immunohistochemistry techniques in each of the major ganglia: the eyestalk ganglia, the central brain and the thoracic ganglion. Western blots yielded two bands for the crab NR1-like subunit, at ~88 and ~84 kDa. This subunit is present in all the major ganglia, and shows a strong localisation in synaptosomal membranes. NMDARs are distributed throughout the majority of each ganglion but show prominent signal intensity in some distinguishable neuropils and neurons. This is the first general description of the Neohelice granulata nervous system as a whole and the first study of NMDARs in the CNS of decapods. The preferential localisation of the receptor in some neuropils and neurons indicates the presence of possible new targets for memory processing and storage.