Olfactory secretion and sodium, potassium-adenosine triphosphatase: Regulation by corticosteroids

Objectives: To investigate the cellular distribution and relative intensity of the immunoreactivity associated with the expression of sodium, potassiu m-adenosine triphosphatase (Na,K-ATPase) in cells of the olfactory mucosa, Second, changes in the activity of this enzyme in the olfactory mucosa are correlated with changes in the circulating corticosteroid aldosterone, Meth ods: Combination of immunohistochemical and biochemical techniques were emp loyed to examine the olfactory Na, K-ATPase. Results: Within the olfactory epithelium, the Na, K-ATPase immunoreactivity was greatest at the supranucl ear region of sustentacular cells and/or dendrites of olfactory receptor ne urons (ORNs). Cell bodies of ORNs demonstrated moderate immunoreactivity, w hereas the duct cells of Bowman's gland exhibited moderate to intense immun oreactivity, Acinar cells of the Bowman's gland were the most intensely sta ined components of the lamina propria, exhibiting strong immunoreactivity a t the basolateral plasma membrane domains of the acinar cells and less with in the cytoplasm, Binding of ouabain, a specific inhibitor of Na, K-ATPase, was significantly elevated for aldosterone-injected versus sham-injected c ontrols. Conclusion: These results suggest that olfactory Na, K-ATPase is r egulated by the systemic corticosteroid aldosterone, The results are consis tent with the hypothesis that corticosteroids regulate olfactory secretion.