J Physiol Society Membership
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
 QUICK SEARCH:   [advanced]


     


J Physiol Vol 295 pp 69-81
Copyright © 1979 by The Physiological Society
This Article
Right arrow Full Text (PDF)
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Attwell, D
Right arrow Articles by Ojeda, C
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Attwell, D
Right arrow Articles by Ojeda, C

The action of salicylate ions on the frog node of Ranvier.

D Attwell, C Bergman and C Ojeda

1. The effects of salicylate on the membrane currents in the frog node of Ranvier were investigated. 2. External salicylate slows the falling phase of the action potential, with little effect on the action potential amplitude. 3. External salicylate has no effect on the leak current. 4. Most of the actions of external salicylate can be attributed to a simple incorporation of negative charge into the membrane surface. The h infinity, tau h, tau m and m infinity curves for the sodium current are shifted to more negative potentials, as are the n infinity and k infinity curves for the potassium current. Potassium ion accumulation prevented analysis of the action of salicylate on the time constant of the potassium current kinetics. 5. In addition to the h infinity and tau h curves being shifted to more negative potentials, the shapes of the curves are also changed by salicylate. These shape changes cannot be explained by conventional homogeneous surface charge theory. Possible explanations for these changes are discussed. 6. Internal salicylate has similar effects to external salicylate: the gating variable curves for the sodium current are shifted in the negative direction on the voltage axis, rather than in the positive direction expected if negative charge were added to the inner surface of the nodal membrane. This may be due to salicylate crossing the membrane and binding preferentially to a receptor at the external surface, or might be due to a rise in intracellular calcium concentration following inhibition of oxidative phosphorylation.







HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1979 The Physiological Society.