Na(+)/K(+) -ATPase as a marker for detecting pulmonary sensory receptors

Pulmonary vagal afferents provide some of the most important breathing control inputs to the respiratory center. However, the structure of vagal receptors is not yet well known. Lack of an available and effective method to identify pulmonary receptors is the major limiting factor. Here we describe a new approach using confocal microscopy to examine the structure of immunohistochemically stained airway receptors by using Na(+)/K(+)-ATPase as a marker. This method permits detailed observation of pulmonary receptor structures and their relationship to target tissue in the rabbit. The parent axon has multiple branches that supply the receptor structure. Each structure has multiple endings that form leaf-like terminals. This technique permits examining pulmonary receptor structures in detail, and should assist in identifying the morphology of the receptors and the mechanisms of receptor activation.