Institute of Development, Aging and Cancer, Tohoku University

Research

Seminars and Symposia

IDAC Seminar, 19 March 2015

Secretariat, Alumni Association, IDAC
Date Thursday ,19 March 2015, 18:30~
Room Smart Ageing Research Building International Conference Room
Title Neural stem cells in the carotid body. Role in adaptation to hypoxia
Speaker Dr. Jose Lopez-Barneo
Affiliation Institute of Biomedicine of Seville, University of Seville
Person-in-charge Takashi Kondo (Department of Thoracic Surgery)
Contact: Yasushi Hoshikawa (ex:8521)
Abstract Peripheral chemoreceptors (e.g. carotid body (CB)) contain specialized O2-sensitive cells with K+ channels which are inhibited during hypoxia. These cells release transmitters that activate sensory fibers (“chemo-sensory synapses”) conveying the information to the respiratory center thus triggering homeostatic cardiorespiratory reflexes (e.g. hyperventilation and sympathetic activation). During protracted hypoxia the CB grows several folds its normal size thus increasing the excitatory input to the respiratory center. This adaptive response is necessary for acclimatization to hypoxemia, a condition affecting to high altitude sojourners or patients with obstructive lung diseases. CB growth is due to activation of a resident population of adult CB stem cells, which form ”chemo-proliferative” synapses with the O2-sensitive glomus cells. Upon exposure to hypoxia, transmitters released from glomus cells (e.g. endothelin 1) induce stem cell-dependent growth of the CB parenchyma. These findings reveal the mechanisms underlying thus far unexplained fundamental biomedical processes. They may also help expansion of CB tissue in vitro and facilitate its use in cell therapy for Parkinson’s disease.