HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Adrian, R H Articles by Almers, W Search for Related Content PubMed PubMed Citation Articles by Adrian, R H Articles by Almers, W

1. Non-linear polarization currents apparently due to permanent dipoles or mobile charges in the membrane can be measured by appropriate comparison of the transient currents required to produce small and large steps of membrane potential. Integration of these transient polarization currents estimates the charge transfer associated with the movement of membrane dipoles or charges. 2. Depolarization from -100 to 0 mV requires a charge transfer of 35 nC/muF in addition to the charge transfer predicted by linear extrapolation of the charge required for a small depolarization from -100 mV. Depolarizations of varying size give a charge-voltage relation which is sigmoid saturating beyond o mV and with a midpoint at about -50 mV. The ratnged depolarization reduces or removes charge movement detected by comparing currents for small and large voltage steps from -100 mV (Charge 1). However in depolarized fibres comparison of currents from a small potential step at +40 mV and a large hyperpolarizing potential step from -20 mV reveals large movements of a second charge (Charge 2). Movement of Charge 2 is less steeply dependent on voltage than movement of Charge 2 both in magnitude and in rate. 4. In size and voltage dependence these two kinds of charge movement correspond to measured voltage dependence of capacity in normally polarized and depolarized fibres (Adrian & Almers, 1976).