help button home button Biophys. J.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS

Biophysical Journal 19: 177-183 (1977)
© 1977 the Biophysical Society

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
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
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Fishman, H M
Right arrow Articles by Poussart, D
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Fishman, H M
Right arrow Articles by Poussart, D

Asymmetry currents and admittance in squid axons.

H M Fishman, L E Moore and D Poussart

ABSTRACT

The complex admittance of squid (Loligo pealei) axon was measured rapidly (within 1 s) with pseudo-random small signals and discrete Fourier transform techniques under guarded, "space-clamp" conditions and during suppression of ion conduction. Asymmetry currents were measured by paired step clam pulses of +/-70 mV from a holding potential of -97 mV and gave an apparent capacitance of 0.36 muF/cm2. However, the admittance data showed no change in capacitance at holding potentials from -97 to -67 mV and gave a decrease of 0.07 of 0.15 muF/cm2 at -37 mV. The failure to observe a capacitance increase at low membrane potentials suggests the following possibilities: (a) the asymmetry current is a displacement current that inactivates completely with time, and (b) the asymmetry current is not a displacement current and arises from large signal effects (i.e., delayed nonlinearity in ionic current) on the membrane.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1977 by the Biophysical Society.