Reyes Edison Pablo, Cerpa Verónica, Corvalán Liliana, Retamal Mauricio Antonio
Centro de Fisiología Celular e Integrativa, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo Santiago, Chile ; Dirección de Investigación, Universidad Autónoma de Chile Santiago, Chile.
Centro de Fisiología Celular e Integrativa, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo Santiago, Chile.
Front Cell Neurosci. 2014 May 9;8:123. doi: 10.3389/fncel.2014.00123. eCollection 2014.
Connexins (Cxs) and Pannexins (Panx) form hemichannels at the plasma membrane of animals. Despite their low open probability under physiological conditions, these hemichannels release signaling molecules (i.e., ATP, Glutamate, PGE2) to the extracellular space, thus subserving several important physiological processes. Oxygen and CO2 sensing are fundamental to the normal functioning of vertebrate organisms. Fluctuations in blood PO2, PCO2 and pH are sensed at the carotid bifurcations of adult mammals by glomus cells of the carotid bodies. Likewise, changes in pH and/or PCO2 of cerebrospinal fluid are sensed by central chemoreceptors, a group of specialized neurones distributed in the ventrolateral medulla (VLM), raphe nuclei, and some other brainstem areas. After many years of research, the molecular mechanisms involved in chemosensing process are not completely understood. This manuscript will review data regarding relationships between chemosensitive cells and the expression of channels formed by Cxs and Panx, with special emphasis on hemichannels.
连接蛋白（Cxs）和泛连接蛋白（Panx）在动物细胞膜上形成半通道。尽管在生理条件下它们的开放概率较低，但这些半通道会将信号分子（如ATP、谷氨酸、前列腺素E2）释放到细胞外空间，从而参与多种重要的生理过程。氧气和二氧化碳传感对于脊椎动物的正常功能至关重要。成年哺乳动物颈动脉体的球细胞在颈动脉分叉处感知血液中PO2、PCO2和pH的波动。同样，脑脊液pH值和/或PCO2的变化由中枢化学感受器感知，中枢化学感受器是一组分布在延髓腹外侧（VLM）、中缝核及其他一些脑干区域的特殊神经元。经过多年研究，化学传感过程所涉及的分子机制尚未完全明确。本手稿将综述有关化学敏感细胞与由Cxs和Panx形成的通道表达之间关系的数据，特别着重于半通道。
