Long-chain n-alkanols and arachidonic acid interfere with the Vm-sensitive gating mechanism of gap junction channels

Pflugers Arch. 1998 Jan;435(2):310-9. doi: 10.1007/s004240050517.


Experiments were carried out on preformed cell pairs and induced cell pairs of an insect cell line (mosquito Aedes albopictus, clone C6/36). The coupling conductance, gj, was determined with the dual voltage-clamp method. Exposure of preformed cell pairs to lipophilic agents, such as long-chain n-alkanols (n-hexanol, n-heptanol, n-octanol, n-nonanol, n-decanol) or arachidonic acid, provoked a decrease in gj. Hyperpolarization of both cells led to a recovery of gj. Systematic studies revealed that this phenomenon is caused by a shift of the sigmoidal relationship gj(ss) = f(Vm) towards more negative values of Vm (where gj(ss) = conductance at steady-state; Vm = membrane potential). The shift was dose dependent, it developed with time and was reversible. The longer the hydrocarbon chain of n-alkanols, the lower was the concentration required to produce a given shift. Besides shifting the function gj(ss) = f(Vm), arachidonic acid decreased the maximal conductance, gj(max). Single-channel records gained from induced cell pairs revealed that the lipophilic agents interfere with the Vm-sensitive slow channel gating mechanism. Application provoked slow current transitions (transition time: 5-40 ms) between an open state of the channel (i.e. main state or residual state) and the closed state; subsequently, fast channel transitions (transition time: < 2 ms) involving the main state and the residual state ceased completely. Hyperpolarization of Vm or washout of the lipophilic agents gave rise to the inverse sequence of events. The single-channel conductances gammaj(main state) and gammaj(residual state) were not affected by n-heptanol. We conclude that long-chain n-alkanols and arachidonic acid interact with the Vm-sensitive gating mechanism.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 1-Octanol / pharmacology
  • Aedes
  • Alcohols / pharmacology*
  • Animals
  • Arachidonic Acid / pharmacology*
  • Cell Line
  • Electric Conductivity
  • Fatty Alcohols / pharmacology
  • Gap Junctions / physiology*
  • Heptanol / pharmacology
  • Hexanols / pharmacology
  • Ion Channel Gating / drug effects*
  • Ion Channels / physiology*
  • Membrane Potentials


  • Alcohols
  • Fatty Alcohols
  • Hexanols
  • Ion Channels
  • Arachidonic Acid
  • 1-hexanol
  • n-decyl alcohol
  • Heptanol
  • 1-Octanol