English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

A number of compounds related to TEA(+) (tetraethylammoniumion) were injected into squid axons and their effects on g(K) (the potassium conductance) were determined. In most of these ions a quaternary nitrogen is surrounded by three ethyl groups and a fourth group that is very hydrophobic. Several of the ions cause inactivation of g(K), a type of ionic gating that is not normally seen in squid axon; i.e., after depolarization g(K) increases and then spontaneously decreases to a small fraction of its peak value even though the depolarization is maintained. Observations on the mechanism of this gating show that (a) QA (quaternary ammonium) ions only enter K(+) channels that have open activation gates (the normal permeability gates). (b) The activation gates of QA-occluded channels do not close readily. (c) Hyperpolarization helps to clear QA ions from the channels. (d) Raising the external K(+) concentration also helps to clear QA ions from the channels. Observations (c) and (d) strongly suggest that K(+) ions traverse the membrane by way of pores, and they cannot be explained by the usual type of carrier model. The data suggest that a K(+) pore has two distinct parts: a wide inner mouth that can accept a hydrated K(+) ion or a TEA(+)-like ion, and a narrower portion that can accept a dehydrated or partially dehydrated K(+) ion, but not TEA(+).

Interaction of Tetraethylammonium Ion Derivatives with the Potassium Channels of Giant Axons