title: Aspartate immunoreactivity in the telencephalon of the adult sea lamprey: comparison with GABA immunoreactivity.
abstract: The excitatory amino acid l-aspartate (Asp) plays a number of roles in neuronal function. We studied the distribution of Asp-immunoreactive (ir) cells in the telencephalon of young and upstream migrating adult sea lamprey, Petromyzon marinus, and compared it with the distribution of gamma-aminobutyric acid (GABA) immunoreactivity, by using double immunofluorescence methods. Our results reveal for the first time the existence of Asp-ir neuronal populations in the lamprey forebrain. In the olfactory bulbs, Asp-ir neurons were observed in the mitral cell layer and in the inner cellular layer. Many granule-like cells were both Asp-ir and GABA-ir. In the pallium, Asp-ir cells were abundant in the lateral pallium and most of them were also GABA-ir. In the septum/terminal lamina nucleus, some cerebrospinal fluid-contacting type (CSF-c) cells were either Asp-ir or GABA-ir, and a few were double-labeled. Some non-CSF-c septal cells were both Asp-ir and GABA-ir. In the striatum, Asp-ir and/or GABA-ir cells were either subependymal or located in the characteristic arched cell row. In the lateral preoptic region, a few small Asp-ir/GABA-ir neurons were observed. In the caudal preoptic recess nucleus, numerous CSF-c cells were Asp-ir and/or GABA-ir. This study also reveals that colocalization of GABA and Asp immunoreactivities in telencephalic neurons is partial. Further investigation is required to establish whether Asp is a neurotransmitter and/or an intermediate in GABA synthesis in lamprey telencephalon.
authors.affiliation: Department of Cell Biology and Ecology, Faculty of Biology, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: Verona
authors.initials: V
authors.lastname: Villar-Cerviño
authors.forename: Antón
authors.initials: A
authors.lastname: Barreiro-Iglesias
authors.forename: Ramón
authors.initials: R
authors.lastname: Anadón
authors.forename: María Celina
authors.initials: MC
authors.lastname: Rodicio
mesh_terms: D000818:Animals; D001224:Aspartic Acid / Q000378:metabolism*; D048428:Petromyzon / Q000033:anatomy & histology* / Q000378:metabolism; D013687:Telencephalon / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
chemical_list: D001224:Aspartic Acid; D005680:gamma-Aminobutyric Acid