title: Carotid body oxygen sensing and adaptation to hypoxia.
abstract: The carotid body (CB) is the principal arterial chemoreceptor that mediates the hyperventilatory response to hypoxia. Our understanding of CB function and its role in disease mechanisms has progressed considerably in the last decades, particularly in recent years. The sensory elements of the CB are the neuron-like glomus cells, which contain numerous transmitters and form synapses with afferent sensory fibers. The activation of glomus cells under hypoxia mainly depends on the modulation of O2-sensitive K(+) channels which leads to cell depolarization and the opening of Ca(2+) channels. This model of sensory transduction operates in all mammalian species studied thus far, including man. However, the molecular mechanisms underlying the modulation of ion channel function by changes in the O2 level are as yet unknown. The CB plays a fundamental role in acclimatization to sustained hypoxia. Mice with CB atrophy or patients who have undergone CB resection due to surgical treatments show a marked intolerance to even mild hypoxia. CB growth under hypoxia is supported by the existence of a resident population of neural crest-derived stem cells of glia-like phenotype. These stem cells are not highly affected by exposure to low O2 tension; however, there are abundant synapse-like contacts between the glomus cells and stem cells (chemoproliferative synapses), which may be needed to trigger progenitor cell proliferation and differentiation under hypoxia. CB hypo- or hyper-activation may also contribute to the pathogenesis of several prevalent human diseases.
authors.affiliation: Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Avenida Manuel Siurot s/n, 41013, Seville, Spain. lbarneo@us.es.|Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, Spain. lbarneo@us.es.|Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain. lbarneo@us.es.
authors.forename: José
authors.initials: J
authors.lastname: López-Barneo
authors.affiliation: Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Avenida Manuel Siurot s/n, 41013, Seville, Spain.|Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Macías
authors.affiliation: Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Avenida Manuel Siurot s/n, 41013, Seville, Spain.|Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, Spain.
authors.forename: Aida
authors.initials: A
authors.lastname: Platero-Luengo
authors.affiliation: Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Avenida Manuel Siurot s/n, 41013, Seville, Spain.|Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, Spain.|Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.
authors.forename: Patricia
authors.initials: P
authors.lastname: Ortega-Sáenz
authors.affiliation: Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Avenida Manuel Siurot s/n, 41013, Seville, Spain.|Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, Spain.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Pardal
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D020013:Calcium Signaling; D002344:Carotid Body / Q000378:metabolism* / Q000502:physiology; D006801:Humans; D000860:Hypoxia / Q000378:metabolism*; D010100:Oxygen / Q000097:blood / Q000378:metabolism*; D015221:Potassium Channels / Q000378:metabolism
chemical_list: D015221:Potassium Channels; D010100:Oxygen
keywords: Acclimatization to hypoxia; Carotid body; Carotid body pathophysiology; Neural crest-derived stem cells; Oxygen sensing