Acute oxygen sensing: diverse but convergent mechanisms in airway and arterial chemoreceptors

Airway neuroepithelial bodies sense changes in inspired O(2), whereas arterial O(2) levels are monitored primarily by the carotid body. Both respond to hypoxia by initiating corrective cardiorespiratory reflexes, thereby optimising gas exchange in the face of a potentially deleterious O(2) supply. One unifying theme underpinning chemotransduction in these tissues is K(+) channel inhibition. However, the transduction components, from O(2) sensor to K(+) channel, display considerable tissue specificity yet result in analogous end points. Here we highlight how emerging data are contributing to a more complete understanding of O(2) chemosensing at the molecular level.