The standard Hodgkin-Huxley model and squid axons in reduced external Ca++ fail to accommodate to slowly rising currents.

Abstract:

:Accommodation may be defined as an increase in the threshold of an excitable membrane when the membrane is subjected to a sustained subthreshold depolarizing stimulus. Some excitable membranes show accommodation in response to currents which rise linearly at a very slow rate. In this report we point out a theoretical and an experimental counterexample, i.e., a nerve model and an axon which do not accommodate. The nerve model is the standard Hodgkin-Huxley axon, which Hodgkin and Huxley expected not to be excited by a very slowly rising current. This expectation is often quoted as fact, in spite of contrary calculations which we confirm. We have found that squid axons in seawater with reduced divalent cation concentration also do not accommodate to slowly rising currents.

journal_name

Biophys J

journal_title

Biophysical journal

authors

Jakobsson E,Guttman R

doi

10.1016/S0006-3495(80)85059-4

subject

Has Abstract

pub_date

1980-08-01 00:00:00

pages

293-7

issue

2

eissn

0006-3495

issn

1542-0086

pii

S0006-3495(80)85059-4

journal_volume

31

pub_type

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