MECHANISM OF THE ELECTROGENIC SODIUM-PUMP DEPENDENCE OF MEMBRANE CHEMOSENSITIVITY

1. 1. The relation of acetyleholine (Ach) induced current of the nerve cell membrane in Helix to electrogenic sodium (Na) pump activity and to the osmolar pressure of the external solution were studied. 2. 2. Inactivation of the Na pump by the reduction in oxygen tension increase Ach-induced current. 3. 3. Both ouabain and K-free solution increase Ach-induced current and Ach-induced membrane conductivity without pronounced changes in the reversal potential for Ach responses. 4. 4. Similarity of the Na pump inactivation and hyposmolar solution effects on the dose-response curves was shown. 5. 5. The results suggest that electrogenic Na pump modulates the membrane chemosensitivity by changing of the membrane surface for transmitter attachment. © 1979.