Palytoxin-induced permeability changes in excitable membranes.

L Lauffer; S Stengelin; L Béress; F Hucho

doi:10.1016/0005-2736(85)90137-3

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Palytoxin-induced permeability changes in excitable membranes.

L Lauffer·S Stengelin·L Béress·F Hucho

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Abstract

Palytoxin, a toxin isolated from the Caribean corrall Palythoa caribaeorum, increases the cation permeability of excitable membranes in vitro. Three membrane systems have been investigated: axonal membranes from crayfish walking leg nerves, membranes rich in nicotinic acetylcholine receptor isolated from Torpedo californica electric tissue and, for control, artificial liposomes. Ion permeability of the latter was not affected by palytoxin, but with both biological membranes an increase in cation permeability was observed at a palytoxin concentration of 0.14 microM. Palytoxin-induced cation flow through the axonal membrane was not inhibited by tetrodotoxin, indicating that the voltage-dependent sodium channels were not involved. The effect of palytoxin on the receptor-rich membranes was not blocked by alpha-bungarotoxin, a competitive antagonist of the nicotinic acetylcholine receptor, nor by triphenylmethylphosphonium, a blocker of the receptor-ion channel. But with both the axonal and the receptor-rich membranes ouabain was an inhibitor of the palytoxin-induced cation flow. Evidence is presented that it is not the (Na+ + K+)-ATPase which is affected by palytoxin as has been postulated for similar observations with non-neuronal membranes (Chhatwal, G.S., Hessler, H.-J. and Habermann, E. (1983) Naunyn-Schmiedeberg's Arch. Pharmacol. 323, 261-268).

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Acrylamides Animals Astacoidea Axons Cell Membrane Permeability Cnidarian Venoms Electric Organ In Vitro Techniques Liposomes Lithium Receptors, Nicotinic Sodium Torpedo Polyether Toxins Journal Article Research Support, Non-U.S. Gov't

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L Lauffer, S Stengelin, L Béress, F Hucho. 1985-08-08. Palytoxin-induced permeability changes in excitable membranes.. https://doi.org/10.1016/0005-2736(85)90137-3

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