title: Cortical and subcortical distribution of ionotropic purinergic receptor subunit type 1 (P2X(1)R) immunoreactive neurons in the rat forebrain.
abstract: Ionotropic purinergic receptors (P2XR) are ATP-gated cationic channels composed of seven known subunits (P2X(1-7)R) and involved in different functions in neural tissue. Although their presence has been demonstrated in the brain, few studies have investigated their expression pattern. In particular, ionotropic purinergic receptor subunit type 1 (P2X(1)R) has been observed in the cerebellum and in brainstem nuclei. The present study investigates the P2X(1)R expression pattern in the rat forebrain using immunohistochemistry. The specificity of the immunolabeling has been verified by Western blotting and in situ hybridization methods. P2X(1)R immunoreactivity was specifically localized in neurons, dendrites and axons throughout the forebrain. Characteristic differences in the distribution of P2X(1)R were observed in different cortical areas. In prefrontal, cingulate and perirhinal cortices, very intense labeling was present in neuronal bodies. In frontal, parietal, temporal and occipital cortices, immunostaining was lighter and mainly found in dendrites and axons. The hippocampal formation was intensely labeled. Labeling was present almost exclusively in dendrites and axons and never in neuronal bodies. The diencephalon was devoid of P2X(1)R positive neurons or fibers except for the medial habenular nucleus, which showed very intense P2X(1)R immunostaining. Furthermore, two subcortical regions, namely, the nucleus centralis of the amygdala and the bed nucleus of the stria terminalis, showed intense P2X(1)R neuronal labeling. Present data indicate that P2X(1)R are prevalent in forebrain areas involved in the integration of cognitive, limbic and autonomic functions.
authors.affiliation: Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.) Santa Lucia Foundation, Via Fosso del Fiorano 64, Rome, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Florenzano
authors.forename: P
authors.initials: P
authors.lastname: Carrive
authors.forename: M T
authors.initials: MT
authors.lastname: Viscomi
authors.forename: F
authors.initials: F
authors.lastname: Ferrari
authors.forename: L
authors.initials: L
authors.lastname: Latini
authors.forename: D
authors.initials: D
authors.lastname: Conversi
authors.forename: S
authors.initials: S
authors.lastname: Cabib
authors.forename: C
authors.initials: C
authors.lastname: Bagni
authors.forename: M
authors.initials: M
authors.lastname: Molinari
mesh_terms: D000818:Animals; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D008297:Male; D009474:Neurons / Q000378:metabolism* / Q000648:ultrastructure; D010751:Phosphopyruvate Hydratase / Q000378:metabolism; D016548:Prosencephalon / Q000166:cytology*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D018048:Receptors, Purinergic P2 / Q000235:genetics / Q000378:metabolism*; D058469:Receptors, Purinergic P2X
chemical_list: D005904:Glial Fibrillary Acidic Protein; D012333:RNA, Messenger; D018048:Receptors, Purinergic P2; D058469:Receptors, Purinergic P2X; D010751:Phosphopyruvate Hydratase