title: Genetically modified mice as a strategy to unravel the role played by the Na(+)/Ca (2+) exchanger in brain ischemia and in spatial learning and memory deficits.
abstract: Because no isoform-specific blocker of NCX has ever been synthesized, a more selective strategy to identify the role of each antiporter isoform in the brain was represented by the generation of knockout and knockin mice for the different isoforms of the antiporter.Experiments performed in NCX2 and NCX3 knockout mice provided evidence that these two isoforms participate in spatial learning and memory consolidation, although in an opposite manner. These new data from ncx2-/- and ncx3-/- mice may open new experimental avenues for the development of effective therapeutic compounds that, by selectively inhibiting or activating these molecular targets, could treat patients affected by cognitive impairment including Alzheimer's, Parkinson's, Huntington's diseases, and infarct dementia.More importantly, knockout and knockin mice also provided new relevant information on the role played by NCX in maintaining the intracellular Na(+) and Ca(2+) homeostasis and in protecting neurons during brain ischemia. In particular, both ncx2-/- and ncx3-/- mice showed an increased neuronal vulnerability after the ischemic insult induced by transient middle cerebral artery occlusion.As the ubiquitous deletion of NCX1 brings about to an early death of embryos because of a lack of heartbeat, this strategy could not be successfully pursued. However, information on the role of NCX1 in normal and ischemic brain could be obtained by developing conditional knockout mice lacking NCX1 in the brain. Preliminarily results obtained in these conditional mice suggest that also NCX1 protects neurons from ischemic cell death.Overall, the use of genetic-modified mice for NCX1, NCX2, and NCX3 represents a fruitful strategy to characterize the physiological role exerted by NCX in CNS and to identify the isoforms of the antiporter as potential molecular targets for therapeutic intervention in cerebral ischemia.
authors.affiliation: Department of Neuroscience, Federico II University of Naples, Naples, Italy.
authors.forename: Pasquale
authors.initials: P
authors.lastname: Molinaro
authors.forename: Mauro
authors.initials: M
authors.lastname: Cataldi
authors.forename: Ornella
authors.initials: O
authors.lastname: Cuomo
authors.forename: Davide
authors.initials: D
authors.lastname: Viggiano
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Pignataro
authors.forename: Rossana
authors.initials: R
authors.lastname: Sirabella
authors.forename: Agnese
authors.initials: A
authors.lastname: Secondo
authors.forename: Francesca
authors.initials: F
authors.lastname: Boscia
authors.forename: Anna
authors.initials: A
authors.lastname: Pannaccione
authors.forename: Antonella
authors.initials: A
authors.lastname: Scorziello
authors.forename: Sophie
authors.initials: S
authors.lastname: Sokolow
authors.forename: André
authors.initials: A
authors.lastname: Herchuelz
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Di Renzo
authors.forename: Lucio
authors.initials: L
authors.lastname: Annunziato
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism / Q000473:pathology; D002545:Brain Ischemia / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007859:Learning Disabilities / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D008569:Memory Disorders / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D018345:Mice, Knockout; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D019636:Neurodegenerative Diseases / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D019831:Sodium-Calcium Exchanger / Q000235:genetics / Q000378:metabolism*
chemical_list: C499849:NCX1 protein, mouse; D009419:Nerve Tissue Proteins; C491739:Slc8a2 protein, mouse; C491101:Slc8a3 protein, mouse; D019831:Sodium-Calcium Exchanger