Sodium/calcium exchanger expression in the mouse and rat olfactory systems.

摘要: Sodium/calcium (Na+/Ca2+) exchangers are membrane transport systems that regulate Ca2+-homeostasis in many eukaryotic cells. In olfactory and vomeronasal sensory neurons ligand-induced signal transduction is associated with influx elevation of intracellular Ca2+, [Ca2+]i. While much effort has been devoted to the characterization Ca2+-related excitation adaptation events chemosensory (OSNs), less known about mechanisms return [Ca2+]i resting state. To identify proteins participating poststimulus Ca2+-clearance mouse OSNs, we analyzed expression three potassium (K+)-independent (NCX1, 2, 3) K+-dependent (NCKX1, Na+/Ca2+ exchangers. situ hybridization showed mRNAs all six coexist systems, some already detectable embryo. Of these, NCX1 NCKX1 represent most least abundant mRNAs, respectively. Moreover, immunohistochemistry revealed NCX1, 3 expressed nearly epithelium, organ, septal organ Masera, Grueneberg ganglion. These exchanger display different profiles dendrites, knobs, plasma membranes OSNs sustentacular Furthermore, show mRNA rat mucosa as 8 alternative splice variants. This first comprehensive analysis mammalian system. Our results suggest Ca2+-extrusion by utilizes multiple subtypes targeted subcellular compartments. J. Comp. Neurol. 501:944–958, 2007. © 2007 Wiley-Liss, Inc.