General anesthetic block of a bifurcating axon

doi:10.1016/0006-8993(82)90350-X

Brain Research

Volume 245, Issue 1, 5 August 1982, Pages 148-153

https://doi.org/10.1016/0006-8993(82)90350-X Get rights and content

Abstract

Axons with a low safety factor for conduction, namely the bifurcating motor neurons of the lobster deep extensor muscles, were tested for sensitivity to general anesthetic agents. Bath concentrations of 100–300 mM diethyl ether or 1.7–3.4 mM halothane were applied. The anesthetics blocked conduction of single action potentials in the branches before the main axon. Maximum following frequency of the branch point itself was reduced before the response to single stimuli was affected. Although the applied concentrations are slightly above those which correspond to general anesthesia, this large axon is relatively more sensitive than others of comparable diameter. These effects may have a role in the mechanism of general anesthesia, since even in the absence of frank conduction block, the pattern of impulse flow through the branch point may be significantly altered.

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General anesthetic block of a bifurcating axon

Abstract

Comp. Biochem. Physiol.

Curr. Mod. Biol.

Modification of sodium and potassium channel gating kinetics by ether and halothane

J. gen. Physiol.

Differential conduction block in branches of a bifurcating axon

J. Physiol. (Lond.)

Ionic mechanisms involved in differential conduction of action potentials at high frequency in a branching axon

J. Physiol. (Lond.)

Synaptic depression related to presynaptic axon conduction block

J. Physiol. (Lond.)

General and local anesthetics: different membrane sites of action

Anesthetics: molecular correlates of voltage and frequency-dependent sodium channel block in nerve

J. Pharmacol. exp. Ther.

Anesthetics inhibit pressure-induced repetitive impulse generation

J. appl. Physiol.

Effects of pressure and anesthetics on conduction and synaptic transmission

J. Pharmacol. exp. Ther.