Neuronal acetylcholine receptor channels from insects: a comparative electrophysiological study.
The channel properties of nicotinic acetylcholine receptor subtypes in the nervous system of insects (Locusta migratoria) have been characterized. Single channel measurements were performed using patch-clamp techniques as well as planar lipid bilayer reconstitution approaches. In reconstitution experiments using receptor-preparations isolated from neuronal membranes by alpha-toxin affinity chromatography, a ligand-gated channel type was found, which showed a high conductance and a short mean lifetime. Patch-clamp experiments on synapse-free somata of isolated nerve cells revealed an acetylcholine-gated channel type with a lower conductance but a longer lifetime. The two different agonist-activated channel types are supposed to represent synaptic and extrasynaptic acetylcholine receptors.
Tareilus
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E
Universität Stuttgart-Hohenheim, Institut für Zoophysiologie, Federal Republic of Germany.
Hanke
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W
Breer
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H
D000818:Animals; D002846:Chromatography, Affinity; D004553:Electric Conductivity; D004594:Electrophysiology; D007313:Insecta / Q000378:metabolism / Q000502:physiology*; D007473:Ion Channels / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D011950:Receptors, Cholinergic / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D014403:Tubocurarine / Q000494:pharmacology
D007473:Ion Channels; D011950:Receptors, Cholinergic; D014403:Tubocurarine