Anales RANF

P6. P URINERGIC S IGNALING IN N ERVOUS S YSTEM P.29 ANATOMIC STUDY OF THE CENTRAL NERVOUS SYSTEM DEVELOPMENT EMPLOYING THE MOUSE STRAIN P2rx7 - EGFP. Felipe Ortega 1,2,3 , Rosa Gomez-Villafuertes 1,2,3 , Luis Puelles 4 & María Teresa Miras- Portugal 1,2,3 . 1 Biochemistry and Molecular Biology Department, Faculty of Veterinary medicine, Complutense University, Ave. Puerta de Hierro s/n, 28040 Madrid, Spain; 2 Institute of Neurochemistry (IUIN), Madrid, Spain; 3 Health Research Institute of the Hospital Clínico San Carlos (IdISSC), Spain; 4 Department of Human Anatomy and IMIB- Arrixaca Institute, School of Medicine, University of Murcia, Murcia, Spain. The development of mammalian central nervous system (CNS) is a complex and dynamic process that requires an accurately orchestrated sequence of genetic, environmental and biochemical events. The generation of neural cells, i.e. neurons, astrocytes and oligodendrocytes, comprise a precise control of crucial processes as cell proliferation, cell fate determination, migration, maturation, synapse formation, network implementation and a final controlled apoptosis to define the correct neuronal number and location. The control of these processes accounts for multiple mechanisms including extracellular signaling molecules. Amongst these regulatory extracellular signaling, the purinergic system is one of the most recently discovered and least investigated. Purinergic signaling is driven by cell-surface purinoceptors (P2 receptors) classified in two different subfamilies, P2X and P2Y receptors. In the CNS, purinergic receptors regulates cell growth and migration during development, modulating, subsequently, glia-glia/neuronal-glia interactions, mechanosensory transduction and control of autonomic functions as the CNS matures. Among the P2 receptors, P2X7 receptor (P2X7R) constitutes one of the most promising target to regulate both physiology and pathology in the brain. However, the lack of specific and reliable technical and pharmacological approaches has classically been one of the major hurdles in the study of purinergic receptors and, in particular, the P2X7R. Transgenic mice expressing fluorescent proteins under the specific promoter of purinergic receptors are tools that facilitates the identification of the expression patterns of individual receptors during development. Specifically, the P2rx7 -EGFP transgenic mice express EGFP immediately downstream of the P2rx7 mouse promoter allowing for a detailed study of its distribution in the CNS. Here, we have employed this mouse strain to perform a comprehensive analysis of the pattern of expression of P2X7R during murine CNS development.